Merge branch 'master' into playback-priority

# Conflicts: # src/renderer/controllers/playback-controller.js # src/renderer/controllers/torrent-list-controller.js # src/renderer/main.js
2017-03-14 19:43:57 -03:00
parent 1e5ac1df9c e5fccd93a8
commit 96e7e83e20
165 changed files with 3881 additions and 2264 deletions
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -1,3 +1,5 @@
+<!-- DO NOT POST LINKS OR REFERENCES TO COPYRIGHTED CONTENT IN YOUR ISSUE. -->
+
 **What version of WebTorrent Desktop?** (See the 'About WebTorrent' menu)

 **What operating system and version?**
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
 node_modules/
 build/
 dist/
-npm-debug.log.*
+npm-debug.log*
--- a/.nodemonignore
+++ b/.nodemonignore
@@ -1,2 +0,0 @@
-build/
-dist/
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,4 @@
 language: node_js
 node_js:
  - 'node'
-install: npm install standard
+install: npm install standard depcheck walk-sync
--- a/AUTHORS.md
+++ b/AUTHORS.md
@@ -28,5 +28,14 @@
 - Rémi Jouannet (remijouannet@gmail.com)
 - Andrea Tupini (tupini07@gmail.com)
 - grunjol (grunjol@gmail.com)
+- Jason Kurian (jasonk92@gmail.com)
+- Vamsi Krishna Avula (vamsi_ism@outlook.com)
+- Noam Okman (noamokman@gmail.com)
+- PurgingPanda (t3ch0wn3r@gmail.com)
+- Kai Curtis (morecode@kcurtis.com)
+- Omri Litov (omrilitov@gmail.com)
+- Alexey Romanov (romanalexey@gmail.com)
+- Karan Thakkar (karanjthakkar@gmail.com)
+- Nuno Campos (nuno.campos@me.com)

 #### Generated by bin/update-authors.sh.
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,18 +1,139 @@
 # WebTorrent Desktop Version History

+## v0.18.0
+
+### Added
+- Add a new "Transfers" menu for pausing or resuming all torrents (#1027)
+
+### Changed
+- Update Electron to 1.4.15
+  - Windows 32-bit: App can use 4GB of memory instead of just 2GB
+  - Fix "Portable App" writing crash reports to "%APPDATA%\Temp" (Windows)
+- Updated WebTorrent engine to 0.98.5
+  - Fix issue where http web seeds would sometimes stall
+  - Don't send 'completed' event to tracker again if torrent is already complete
+  - Add more peer ID entropy
+  - Set user-agent header for tracker http requests
+
+### Fixed
+- Fix paste shortcut in tracker list on Create Torrent page (#1112)
+- Auto-focus the 'OK' button in modal dialogs (#1058)
+- Fix formatting issue in the speed stats on the Player page (#1039)
+
+## v0.17.2 - 2016-10-10
+
+### Fixed
+- Windows: Fix impossible-to-delete "Wired CD" default torrent
+- Throttle browser-window 'move' and 'resize' events
+- Fix crash ("Cannot read property 'files' of null" error)
+- Fix crash ("TypeError: Cannot read property 'startPiece' of undefined")
+
+## v0.17.1 - 2016-10-03
+
+### Changed
+- Faster startup (improved by ~25%)
+- Update Electron to 1.4.2
+- Remove support for pasting multiple newline-separated magnet links
+- Reduce UX sound volume
+
+### Fixed
+- Fix external player (VLC, etc.) opening before HTTP server was ready
+- Windows (Portable App): Fix "Portable App" mode
+  - Write application support files to the "Portable Settings" folder
+  - Stop writing Electron "single instance" lock file to "%APPDATA%\Roaming\WebTorrent"
+  - Some temp data is still written to "%APPDATA%\Temp" (will be fixed in future version)
+- Don't show pointer cursor on torrent list checkbox
+- Trim extra whitespace from magnet links pasted into "Open Torrent Address" dialog
+- Fix weird outline on 'Create Torrent' button
+
+## v0.17.0 - 2016-09-23
+
+### Added
+- Remember window size and position
+
+### Changed
+- Torrent list redesign
+- Quieter, more subtle sounds
+- Got rid of the play button spinner, now goes to the player immediately
+- Faster startup
+
+### Fixed
+- Fix bug where playback rate could go negative
+- Don't hide header when moused over player controls
+- Fix Delete Data File on Windows
+- Fix a sad, sad bug that resulted in 100+ MB config files
+- Fix app DMG background image
+
+## v0.16.0 - 2016-09-18
+
+### Added
+- **Windows 64-bit support!** ([#931](https://github.com/feross/webtorrent-desktop/pull/931))
+  - Existing 32-bit users will update to 64-bit automatically in next release
+  - 64-bit reduces likelihood of out-of-memory errors by increasing the address space
+
+### Fixed
+- Mac: Fix background image on .DMG
+
+## v0.15.0 - 2016-09-16
+
+### Added
+- Option to start automatically on login
+- Add integration tests
+- Add more detailed telemetry to diagnose "buffer allocation failed"
+
+### Changed
+- Disable playback controls while in external player (#909)
+
+### Fixed
+- Fix several uncaught errors (#889, #891, #892)
+- Update to the latest webtorrent.js, fixing some more uncaught errors
+- Clicking on the "torrent finished" notification works again (#912)
+
+## v0.14.0 - 2016-09-03
+
+### Added
+- Autoplay through all files in a torrent (#871)
+- Torrents now have a progress bar (#844)
+
+### Changed
+- Modals now use Material UI
+- Torrent list style improvements
+
+### Fixed
+- Fix App.js crash in Linux (#882)
+- Fix error on Windows caused by `setBadge` (#867)
+- Don't crash when restarting after adding a magnet link (#869)
+- Restore playback state when reopening player (#877)
+
+## v0.13.1 - 2016-08-31
+
+### Fixed
+- Fixed the Create Torrent page
+
+## v0.13.0 - 2016-08-31
+
+### Added
+- Support .m4a audio
+- Better telemetry: log error versions, report more types of errors
+
+### Changed
+- New look - Material UI. Rewrote Create Torrent and Preferences pages.
+
+### Fixed
+- Fixed telemetry [object Object] and [object HTMLMediaElement] bugs
+- Don't render player controls when playing externally, eg in VLC
+- Don't play notification sounds during media playback
+
 ## v0.12.0 - 2016-08-23

 ### Added
-
 - Custom external media player
 - Linux: add system-wide launcher and icons for Debian, including Ubuntu

 ### Changed
-
 - Telemetry improvements: redact stacktraces, log app version

 ### Fixed
-
 - Fix playback and download of default torrents ("missing path" error) (#804)
 - Fix Delete Torrent + Data for newly added magnet links
 - Fix jumpToTime error (#804)
@@ -25,13 +146,11 @@
 - Check for missing default download path and torrent folders on start up (#776)

 ### Changed
-
 - Do not automatically set WebTorrent as the default handler for torrents (#771)
 - Torrents can only be created from the home screen (#770)
 - Update Electron to 1.3.3 (#772)

 ### Fixed
-
 - Allow modifying the default tracker list on the Create Torrent page (#775)
 - Prevent opening multiple stacked Preference windows or Create Torrent windows (#770)
 - Windows: Player window auto-resize does not match video aspect ratio (#565)
@@ -40,13 +159,11 @@
 ## v0.10.0 - 2016-08-05

 ### Added
-
 - Drag-and-drop magnet links (selected text) is now supported (#284)
 - Windows: Add "User Tasks" shortcuts to app icon in Start Menu (#114)
 - Linux: Show badge count for completed torrent downloads

 ### Changed
-
 - Change WebTorrent Desktop peer ID prefix to 'WD' to distinguish from WebTorrent in the browser, 'WW' (#688)
 - Switch UI to React to improve UI rendering speed (#729)
  - The primary bottleneck was actually `hyperx`, not `virtual-dom`.
@@ -63,7 +180,6 @@
  - Location history abstraction released independently as [`location-history`](https://www.npmjs.com/package/location-history)

 ### Fixed
-
 - When streaming to VLC, set VLC window title to torrent file name (#746)
 - Fix "Cannot read property 'numPiecesPresent' of undefined" exception (#695)
 - Fix rare case where config file could not be completely written (#733)
@@ -71,35 +187,29 @@
 ## v0.9.0 - 2016-07-20

 ### Added
-
 - Save selected subtitles
 - Ask for confirmation before deleting torrents
 - Support Debian Jessie

 ### Changed
-
 - Only send telemetry in production
 - Clean up the code. Split main.js, refactor lots of things

 ### Fixed
-
 - Fix state.playing.jumpToTime behavior
 - Remove torrent file and poster image when deleting a torrent

 ## v0.8.1 - 2016-06-24

 ### Added
-
 - New URI handler: stream-magnet

 ### Fixed
-
 - DLNA crashing bug

 ## v0.8.0 - 2016-06-23

 ### Added
-
 - Cast menu: choose which Chromecast, Airplay, or DLNA device you want to use
 - Telemetry: send basic data, plus stats on how often the play button works
 - Make posters from jpeg files, not just jpg
@@ -107,17 +217,14 @@
 - Windows thumbnail bar with a play/pause button

 ### Changed
-
 - Nicer modal styles

 ### Fixed
-
 - Windows tray icon now stays in the right state

 ## v0.7.2 - 2016-06-02

 ### Fixed
-
 - Fix exception that affects users upgrading from v0.5.1 or older
  - Ensure `state.saved.prefs` configuration exists
 - Fix window title on "About WebTorrent" window
@@ -125,23 +232,19 @@
 ## v0.7.1 - 2016-06-02

 ### Changed
-
 - Change "Step Forward" keyboard shortcut to `Alt+Left` (Windows)
 - Change "Step Backward" keyboard shortcut to to `Alt+Right` (Windows)

 ### Fixed
-
 - First time startup bug -- invalid torrent/poster paths

 ## v0.7.0 - 2016-06-02

 ### Added
-
 - Improved AirPlay support -- using the new [`airplayer`](https://www.npmjs.com/package/airplayer) package
 - Remember volume setting in player, for as long as the app is open

 ### Changed
-
 - Add (+) button now also accepts non .torrent files and creates a torrent from
  those files
 - Show prompt text in title bar for open dialogs (OS X)
@@ -151,7 +254,6 @@
  - Fix crash reporter not working (Windows)

 ### Fixed
-
 - Re-enable WebRTC (web peers)! (OS X, Windows)
  - Windows support was disabled in v0.6.1 to work around a bug in Electron
  - OS X support was disabled in v0.4.0 to work around a 100% CPU bug
@@ -162,7 +264,6 @@
 - Fix torrent loading message UI misalignment

 ### Known issues
-
 - When upgrading to WebTorrent Desktop v0.7.0, some torrent metadata (file list,
  selected files, whether torrent is streamable) will be cleared. Just start the
  torrent to re-populate the metadata.
@@ -170,7 +271,6 @@
 ## v0.6.1 - 2016-05-26

 ### Fixed
-
 - Disable WebRTC to work around Electron crash (Windows)
  - Will be re-enabled in the next version of WebTorrent, which will be based on
    the next version of Electron, where the bug is fixed.
@@ -182,7 +282,6 @@
 ## v0.6.0 - 2016-05-24

 ### Added
-
 - Added Preferences page to set Download folder
 - Save video position, resume playback from saved position
 - Add additional video player keyboard shortcuts (#275)
@@ -192,7 +291,6 @@
 - Add announcement feature

 ### Changed
-
 - Nicer player UI
 - Reduce startup jank, improve startup time (#568)
 - Cleanup unsupported codec detection (#569, #570)
@@ -200,7 +298,6 @@
 - Improve subtitle positioning (#551)

 ### Fixed
-
 - Fix Uncaught TypeError: Cannot read property 'update' of undefined (#567)
 - Fix bugs in LocationHistory
  - When player is active, and magnet link is pasted, go back to list
@@ -211,23 +308,19 @@
 ## v0.5.1 - 2016-05-18

 ### Fixed
-
 - Fix auto-updater (OS X, Windows).

 ## v0.5.0 - 2016-05-17

 ### Added
-
 - Select/deselect individual files to torrent.
 - Automatically include subtitle files (.srt, .vtt) from torrent in the subtitles menu.
 - "Add Subtitle File..." menu item.

 ### Changed
-
 - When manually adding subtitle track(s), always switch to the new track.

 ### Fixed
-
 - Magnet links throw exception on app launch. (OS X)
 - Multi-file torrents would not seed in-place, were copied to Downloads folder.
 - Missing 'About WebTorrent' menu item. (Windows)
@@ -236,7 +329,6 @@
 ## v0.4.0 - 2016-05-13

 ### Added
-
 - Better Windows support!
  - Windows 32-bit build.
  - Windows Portable App build.
@@ -259,7 +351,6 @@
 - New default torrent on first launch: The WIRED CD.

 ### Changed
-
 - Improve app startup time by 40%.
 - UI tweaks: Reduce font size, reduce torrent list item height.
 - Add Playback menu for playback-related functionality.
@@ -270,7 +361,6 @@
 - Remove "Add Fake Airplay/Chromecast" menu items.

 ### Fixed
-
 - Disable WebRTC to fix 100% CPU usage/crashes caused by Chromium issue. This is
  temporary. (OS X)
 - When fullscreen, make controls use the full window. (OS X)
@@ -295,24 +385,20 @@ to this release!
 ## v0.3.3 - 2016-04-07

 ### Fixed
-
 - App icon was incorrect (OS X)

 ## v0.3.2 - 2016-04-07

 ### Added
-
 - Register WebTorrent as default handler for magnet links (OS X)

 ### Changed
-
 - Faster startup time (50ms)
 - Update Electron to 0.37.5
  - Remove the white flash when loading pages and resizing the window
  - Fix crash when sending IPC messages

 ### Fixed
-
 - Fix installation bugs with .deb file (Linux)
 - Pause audio reliably when closing the window
 - Enforce minimimum window size when resizing player (for audio-only .mov files, which are 0x0)
@@ -320,17 +406,14 @@ to this release!
 ## v0.3.1 - 2016-04-06

 ### Added
-
 - Add crash reporter to torrent engine process

 ### Fixed
-
 - Fix cast screen background: cover, don't tile

 ## v0.3.0 - 2016-04-06

 ### Added
-
 - **Ubuntu/Debian support!** (.deb installer)
 - **DLNA streaming support**
 - Add "File > Quit" menu item (Linux)
@@ -338,14 +421,12 @@ to this release!
 - Crash reporting

 ### Changed
-
 - On startup, do not re-verify files when timestamps are unchanged
 - Moved torrent engine to an independent process, for better UI performance
 - Removed media queries (UI resizing based on window width)
 - Improved Chromecast icon, when connected

 ### Fixed
-
 - "Download Complete" notification shows consistently
 - Create new torrents and seed them without copying to temporary folder
 - Clicking the "Download Complete" notification will always activate app
@@ -364,7 +445,6 @@ Thanks to @dcposch, @grunjol, and @feross for contributing to this release.
 ## v0.2.0 - 2016-03-29

 ### Added
-
 - Minimise to tray (Windows, Linux)
 - Show spinner and download speed when player is stalled waiting for data
 - Highlight window on drag-and-drop
@@ -373,12 +453,10 @@ Thanks to @dcposch, @grunjol, and @feross for contributing to this release.
    Linux users need to download new versions manually.

 ### Changed
-
 - Renamed WebTorrent.app to WebTorrent Desktop
 - Add Cosmos Laundromat as a default torrent

 ### Fixed
-
 - Only capture media keys when player is active
 - Update WebTorrent to 0.88.1 for performance improvements
  - When seeding, do not proactively connect to new peers
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -36,7 +36,7 @@ standard guarded open source project.

 There are a few basic ground-rules for contributors:

-1. **No `--force` pushes** or modifying the Git history in any way.
+1. **No `--force` pushes to master** or modifying history in any way. Rebasing and force pushing your own PR branch is fine.
 2. **Non-master branches** should be used for ongoing work.
 3. **Significant modifications** like API changes should be subject to a **pull request**
   to solicit feedback from other contributors.
@@ -74,6 +74,99 @@ By making a contribution to this project, I certify that:
  including my sign-off) is maintained indefinitely and may be redistributed consistent
  with this project or the open source license(s) involved.

+## Release Procedure
+
+### 1. Create a new version
+
+- Update `AUTHORS`
+
+  ```
+  npm run update-authors
+  ```
+
+  Commit if necessary. The commit message should be "authors".
+
+- Write the changelog
+
+  You can use `git log --oneline <last version tag>..HEAD` to get a list of changes.
+
+  Summarize them concisely in `CHANGELOG.md`. The commit  message should be "changelog".
+
+- Update the version
+
+  ```
+  npm version [major|minor|patch]
+  ```
+
+  This creates both a commit and a git tag.
+
+- Make a PR
+
+  Once the PR is reviewed, merge it:
+
+  ```
+  git push origin <branch-name>:master
+  ```
+
+  This makes it so that the commit hash on master matches the commit hash of the version tag.
+
+  Finally, run:
+
+  ```
+  git push --tags
+  ```
+
+### 2. Create the release binaries
+
+- On a Mac:
+
+  ```
+  npm run package -- darwin --sign
+  npm run package -- linux --sign
+  ```
+
+- On Windows, or in a Windows VM:
+
+  ```
+  npm run package -- win32 --sign
+  ```
+
+- Then, upload the release binaries to Github:
+
+  ```
+  npm run gh-release
+  ```
+
+  Follow the URL to a newly created Github release page. Manually upload the binaries from
+  `webtorrent-desktop/dist/`. Open the previous release in another tab, and make sure that you
+  are uploading the same set of files, no more, no less.
+
+### 3. Test it
+
+**This is the most important part.**
+
+ - Manually download the binaries for each platform from Github.
+
+  **Do not use your locally built binaries.** Modern OSs treat executables differently if they've
+  been downloaded, even though the files are byte for byte identical. This ensures that the
+  codesigning worked and is valid.
+
+- Smoke test WebTorrent Desktop on each platform.
+
+  See Smoke Tests below for details. Open DevTools
+  on Windows and Mac, and ensure that the auto updater is running. If the auto updater does not
+  run, users will successfully auto update to this new version, and then be stuck there forever.
+
+### 4. Ship it
+
+- Update the website
+
+  Create a pull request in [webtorrent.io](https://github.com/feross/webtorrent.io). Update
+  `config.js`, updating the desktop app version.
+
+  As soon as this PR is merged, Jenkins will automatically redeploy the WebTorrent website, and
+  hundreds of thousands of users around the world will start auto updating. **Merge with care.**
+
 ## Smoke Tests

 Before a release, check that the following basic use cases work correctly:
--- a/README.md
+++ b/README.md
@@ -1,6 +1,8 @@
 <h1 align="center">
  <br>
-  <a href="https://webtorrent.io"><img src="https://webtorrent.io/img/WebTorrent.png" alt="WebTorrent" width="200"></a>
+  <a href="https://webtorrent.io">
+    <img src="https://webtorrent.io/img/WebTorrent.png" alt="WebTorrent" width="200">
+  </a>
  <br>
  WebTorrent Desktop
  <br>
@@ -10,9 +12,15 @@
 <h4 align="center">The streaming torrent app. For Mac, Windows, and Linux.</h4>

 <p align="center">
-  <a href="https://gitter.im/feross/webtorrent"><img src="https://img.shields.io/badge/gitter-join%20chat%20%E2%86%92-brightgreen.svg" alt="Gitter"></a>
-  <a href="https://travis-ci.org/feross/webtorrent-desktop"><img src="https://img.shields.io/travis/feross/webtorrent-desktop/master.svg" alt="Travis"></a>
-  <a href="https://github.com/feross/webtorrent-desktop/releases"><img src="https://img.shields.io/github/release/feross/webtorrent-desktop.svg" alt="Release"></a>
+  <a href="https://gitter.im/feross/webtorrent">
+    <img src="https://img.shields.io/badge/gitter-join%20chat%20%E2%86%92-brightgreen.svg" alt="Gitter">
+  </a>
+  <a href="https://travis-ci.org/feross/webtorrent-desktop">
+    <img src="https://img.shields.io/travis/feross/webtorrent-desktop/master.svg" alt="Travis">
+  </a>
+  <a href="https://github.com/feross/webtorrent-desktop/releases">
+    <img src="https://img.shields.io/github/release/feross/webtorrent-desktop.svg" alt="Release">
+  </a>
 </p>

 ## Install
@@ -56,6 +64,38 @@ Restart the app automatically every time code changes. Useful during development
 $ npm run watch
 ```

+### Run linters
+
+```
+$ npm test
+```
+
+### Run integration tests
+
+```
+$ npm run test-integration
+```
+
+The integration tests use Spectron and Tape. They click through the app, taking screenshots and
+comparing each one to a reference. Why screenshots?
+
+* Ad-hoc checking makes the tests a lot more work to write
+* Even diffing the whole HTML is not as thorough as screenshot diffing. For example, it wouldn't
+  catch an bug where hitting ESC from a video doesn't correctly restore window size.
+* Chrome's own integration tests use screenshot diffing iirc
+* Small UI changes will break a few tests, but the fix is as easy as deleting the offending
+  screenshots and running the tests, which will recreate them with the new look.
+* The resulting Github PR will then show, pixel by pixel, the exact UI changes that were made! See
+  https://github.com/blog/817-behold-image-view-modes
+
+For MacOS, you'll need a Retina screen for the integration tests to pass. Your screen should have
+the same resolution as a 2016 12" Macbook.
+
+For Windows, you'll need Windows 10 with a 1366x768 screen.
+
+When running integration tests, keep the mouse on the edge of the screen and don't touch the mouse
+or keyboard while the tests are running.
+
 ### Package the app

 Builds app binaries for Mac, Linux, and Windows.
@@ -84,7 +124,7 @@ The following optional arguments are available:
   - `all` - All platforms (default)

 Note: Even with the `--package` option, the auto-update files (.nupkg for Windows,
-*-darwin.zip for Mac) will always be produced.
+-darwin.zip for Mac) will always be produced.

 #### Windows build notes

--- a/bin/check-deps.js
+++ b/bin/check-deps.js
@@ -1,108 +0,0 @@
-#!/usr/bin/env node
-
-var fs = require('fs')
-var cp = require('child_process')
-
-// We can't use `builtin-modules` here since our TravisCI
-// setup expects this file to run with no dependencies
-var BUILT_IN_NODE_MODULES = [
-  'assert',
-  'buffer',
-  'child_process',
-  'cluster',
-  'console',
-  'constants',
-  'crypto',
-  'dgram',
-  'dns',
-  'domain',
-  'events',
-  'fs',
-  'http',
-  'https',
-  'module',
-  'net',
-  'os',
-  'path',
-  'process',
-  'punycode',
-  'querystring',
-  'readline',
-  'repl',
-  'stream',
-  'string_decoder',
-  'timers',
-  'tls',
-  'tty',
-  'url',
-  'util',
-  'v8',
-  'vm',
-  'zlib'
-]
-
-var BUILT_IN_ELECTRON_MODULES = [ 'electron' ]
-
-var BUILT_IN_DEPS = [].concat(BUILT_IN_NODE_MODULES, BUILT_IN_ELECTRON_MODULES)
-
-var EXECUTABLE_DEPS = [
-  'babel-cli',
-  'babel-plugin-syntax-jsx',
-  'babel-plugin-transform-es2015-destructuring',
-  'babel-plugin-transform-object-rest-spread',
-  'babel-plugin-transform-react-jsx',
-  'gh-release',
-  'nodemon',
-  'standard'
-]
-
-main()
-
-// Scans codebase for missing or unused dependencies. Exits with code 0 on success.
-function main () {
-  if (process.platform === 'win32') {
-    console.error('Sorry, check-deps only works on Mac and Linux')
-    return
-  }
-
-  var usedDeps = findUsedDeps()
-  var packageDeps = findPackageDeps()
-
-  var missingDeps = usedDeps.filter(
-    (dep) => !includes(packageDeps, dep) && !includes(BUILT_IN_DEPS, dep)
-  )
-  var unusedDeps = packageDeps.filter(
-    (dep) => !includes(usedDeps, dep) && !includes(EXECUTABLE_DEPS, dep)
-  )
-
-  if (missingDeps.length > 0) {
-    console.error('Missing package dependencies: ' + missingDeps)
-  }
-  if (unusedDeps.length > 0) {
-    console.error('Unused package dependencies: ' + unusedDeps)
-  }
-  if (missingDeps.length + unusedDeps.length > 0) {
-    process.exitCode = 1
-  }
-}
-
-// Finds all dependencies specified in `package.json`
-function findPackageDeps () {
-  var pkg = JSON.parse(fs.readFileSync('package.json', 'utf8'))
-
-  var deps = Object.keys(pkg.dependencies)
-  var devDeps = Object.keys(pkg.devDependencies)
-  var optionalDeps = Object.keys(pkg.optionalDependencies)
-
-  return [].concat(deps, devDeps, optionalDeps)
-}
-
-// Finds all dependencies that used with `require()`
-function findUsedDeps () {
-  var stdout = cp.execSync('./bin/list-deps.sh')
-  return stdout.toString().trim().split('\n')
-}
-
-function includes (arr, elem) {
-  return arr.indexOf(elem) >= 0
-}
--- a/bin/clean.js
+++ b/bin/clean.js
@@ -5,13 +5,13 @@
 * Useful for developers.
 */

-var fs = require('fs')
-var os = require('os')
-var path = require('path')
-var rimraf = require('rimraf')
+const fs = require('fs')
+const os = require('os')
+const path = require('path')
+const rimraf = require('rimraf')

-var config = require('../src/config')
-var handlers = require('../src/main/handlers')
+const config = require('../src/config')
+const handlers = require('../src/main/handlers')

 // First, remove generated files
 rimraf.sync('build/')
@@ -21,11 +21,11 @@ rimraf.sync('dist/')
 rimraf.sync(config.CONFIG_PATH)

 // Remove any temporary files
-var tmpPath
+let tmpPath
 try {
  tmpPath = path.join(fs.statSync('/tmp') && '/tmp', 'webtorrent')
 } catch (err) {
-  tmpPath = path.join(os.tmpDir(), 'webtorrent')
+  tmpPath = path.join(os.tmpdir(), 'webtorrent')
 }
 rimraf.sync(tmpPath)

--- a/bin/cmd.js
+++ b/bin/cmd.js
@@ -1,10 +0,0 @@
-#!/usr/bin/env node
-
-var electron = require('electron')
-var cp = require('child_process')
-var path = require('path')
-
-var child = cp.spawn(electron, [path.join(__dirname, '..')], {stdio: 'inherit'})
-child.on('close', function (code) {
-  process.exitCode = code
-})
--- a/bin/extra-lint.js
+++ b/bin/extra-lint.js
@@ -0,0 +1,46 @@
+#!/usr/bin/env node
+
+const walkSync = require('walk-sync')
+const fs = require('fs')
+const path = require('path')
+
+let hasErrors = false
+
+// Find all Javascript source files
+const files = walkSync('src', {globs: ['**/*.js']})
+console.log('Running extra-lint on ' + files.length + ' files...')
+
+// Read each file, line by line
+files.forEach(function (file) {
+  const filepath = path.join('src', file)
+  const lines = fs.readFileSync(filepath, 'utf8').split('\n')
+
+  lines.forEach(function (line, i) {
+    let error
+
+    // Consistent JSX tag closing
+    if (line.match(/' {2}\/> *$/) ||
+      line.match('[^ ]/> *$') ||
+      line.match(' > *$')) {
+      error = 'JSX tag spacing'
+    }
+
+    // No lines over 100 characters
+    if (line.length > 100) {
+      error = 'Line >100 chars'
+    }
+
+    if (line.match(/^var /) || line.match(/ var /)) {
+      error = 'Use const or let'
+    }
+
+    if (error) {
+      let name = path.basename(file)
+      console.log('%s:%d - %s:\n%s', name, i + 1, error, line)
+      hasErrors = true
+    }
+  })
+})
+
+if (hasErrors) process.exit(1)
+else console.log('Looks good!')
--- a/bin/list-deps.sh
+++ b/bin/list-deps.sh
@@ -1,10 +0,0 @@
-#!/bin/sh
-# This is a truly heinous hack, but it works pretty nicely.
-# Find all modules we're requiring---even conditional requires.
-
-grep "require('" src/ bin/ -R |
-    grep '.js:' |
-    sed "s/.*require('\([^'\/]*\).*/\1/" |
-    grep -v '^\.' |
-    sort |
-    uniq
--- a/bin/open-config.js
+++ b/bin/open-config.js
@@ -1,6 +1,6 @@
 #!/usr/bin/env node

-var config = require('../src/config')
-var open = require('open')
+const config = require('../src/config')
+const open = require('open')

 open(config.CONFIG_PATH)
--- a/bin/package.js
+++ b/bin/package.js
@@ -1,28 +1,29 @@
 #!/usr/bin/env node

 /**
- * Builds app binaries for Mac, Linux, and Windows.
+ * Builds app binaries for Mac, Windows, and Linux.
 */

-var cp = require('child_process')
-var electronPackager = require('electron-packager')
-var fs = require('fs')
-var minimist = require('minimist')
-var mkdirp = require('mkdirp')
-var os = require('os')
-var path = require('path')
-var rimraf = require('rimraf')
-var series = require('run-series')
-var zip = require('cross-zip')
+const cp = require('child_process')
+const electronPackager = require('electron-packager')
+const fs = require('fs')
+const minimist = require('minimist')
+const mkdirp = require('mkdirp')
+const os = require('os')
+const path = require('path')
+const rimraf = require('rimraf')
+const series = require('run-series')
+const zip = require('cross-zip')

-var config = require('../src/config')
-var pkg = require('../package.json')
+const config = require('../src/config')
+const pkg = require('../package.json')

-var BUILD_NAME = config.APP_NAME + '-v' + config.APP_VERSION
-var BUILD_PATH = path.join(config.ROOT_PATH, 'build')
-var DIST_PATH = path.join(config.ROOT_PATH, 'dist')
+const BUILD_NAME = config.APP_NAME + '-v' + config.APP_VERSION
+const BUILD_PATH = path.join(config.ROOT_PATH, 'build')
+const DIST_PATH = path.join(config.ROOT_PATH, 'dist')
+const NODE_MODULES_PATH = path.join(config.ROOT_PATH, 'node_modules')

-var argv = minimist(process.argv.slice(2), {
+const argv = minimist(process.argv.slice(2), {
  boolean: [
    'sign'
  ],
@@ -36,14 +37,20 @@ var argv = minimist(process.argv.slice(2), {
 })

 function build () {
+  console.log('Reinstalling node_modules...')
+  rimraf.sync(NODE_MODULES_PATH)
+  cp.execSync('npm install', { stdio: 'inherit' })
+  cp.execSync('npm dedupe', { stdio: 'inherit' })
+
+  console.log('Nuking dist/ and build/...')
  rimraf.sync(DIST_PATH)
  rimraf.sync(BUILD_PATH)

-  console.log('Babel: Building JSX...')
+  console.log('Build: Transpiling to ES5...')
  cp.execSync('npm run build', { NODE_ENV: 'production', stdio: 'inherit' })
-  console.log('Babel: Built JSX.')
+  console.log('Build: Transpiled to ES5.')

-  var platform = argv._[0]
+  const platform = argv._[0]
  if (platform === 'darwin') {
    buildDarwin(printDone)
  } else if (platform === 'win32') {
@@ -61,7 +68,7 @@ function build () {
  }
 }

-var all = {
+const all = {
  // The human-readable copyright line for the app. Maps to the `LegalCopyright` metadata
  // property on Windows, and `NSHumanReadableCopyright` on Mac.
  'app-copyright': config.APP_COPYRIGHT,
@@ -73,11 +80,11 @@ var all = {
  // Package the application's source code into an archive, using Electron's archive
  // format. Mitigates issues around long path names on Windows and slightly speeds up
  // require().
-  asar: true,
-
-  // A glob expression, that unpacks the files with matching names to the
-  // "app.asar.unpacked" directory.
-  'asar-unpack': 'WebTorrent*',
+  asar: {
+    // A glob expression, that unpacks the files with matching names to the
+    // "app.asar.unpacked" directory.
+    unpack: 'WebTorrent*'
+  },

  // The build version of the application. Maps to the FileVersion metadata property on
  // Windows, and CFBundleVersion on Mac. Note: Windows requires the build version to
@@ -89,7 +96,7 @@ var all = {

  // Pattern which specifies which files to ignore when copying files to create the
  // package(s).
-  ignore: /^\/src|^\/dist|\/(appveyor.yml|\.appveyor.yml|\.github|appdmg|AUTHORS|CONTRIBUTORS|bench|benchmark|benchmark\.js|bin|bower\.json|component\.json|coverage|doc|docs|docs\.mli|dragdrop\.min\.js|example|examples|example\.html|example\.js|externs|ipaddr\.min\.js|Makefile|min|minimist|perf|rusha|simplepeer\.min\.js|simplewebsocket\.min\.js|static\/screenshot\.png|test|tests|test\.js|tests\.js|webtorrent\.min\.js|\.[^\/]*|.*\.md|.*\.markdown)$/,
+  ignore: /^\/src|^\/dist|\/(appveyor.yml|\.appveyor.yml|\.github|appdmg|AUTHORS|CONTRIBUTORS|bench|benchmark|benchmark\.js|bin|bower\.json|component\.json|coverage|doc|docs|docs\.mli|dragdrop\.min\.js|example|examples|example\.html|example\.js|externs|ipaddr\.min\.js|Makefile|min|minimist|perf|rusha|simplepeer\.min\.js|simplewebsocket\.min\.js|static\/screenshot\.png|test|tests|test\.js|tests\.js|webtorrent\.min\.js|\.[^/]*|.*\.md|.*\.markdown)$/,

  // The application name.
  name: config.APP_NAME,
@@ -104,15 +111,15 @@ var all = {
  // "devDependencies" before starting to package the app.
  prune: true,

-  // The Electron version with which the app is built (without the leading 'v')
-  version: require('electron/package.json').version
+  // The Electron version that the app is built with (without the leading 'v')
+  electronVersion: require('electron/package.json').version
 }

-var darwin = {
+const darwin = {
  // Build for Mac
  platform: 'darwin',

-  // Build 64 bit binaries only.
+  // Build x64 binaries only.
  arch: 'x64',

  // The bundle identifier to use in the application's plist (Mac only).
@@ -129,15 +136,15 @@ var darwin = {
  icon: config.APP_ICON + '.icns'
 }

-var win32 = {
+const win32 = {
  // Build for Windows.
  platform: 'win32',

-  // Build 32 bit binaries only.
-  arch: 'ia32',
+  // Build ia32 and x64 binaries.
+  arch: ['ia32', 'x64'],

  // Object hash of application metadata to embed into the executable (Windows only)
-  'version-string': {
+  win32metadata: {

    // Company that produced the file.
    CompanyName: config.APP_NAME,
@@ -163,12 +170,12 @@ var win32 = {
  icon: config.APP_ICON + '.ico'
 }

-var linux = {
+const linux = {
  // Build for Linux.
  platform: 'linux',

-  // Build 32 and 64 bit binaries.
-  arch: 'all'
+  // Build ia32 and x64 binaries.
+  arch: ['ia32', 'x64']

  // Note: Application icon for Linux is specified via the BrowserWindow `icon` option.
 }
@@ -176,18 +183,18 @@ var linux = {
 build()

 function buildDarwin (cb) {
-  var plist = require('plist')
+  const plist = require('plist')

  console.log('Mac: Packaging electron...')
  electronPackager(Object.assign({}, all, darwin), function (err, buildPath) {
    if (err) return cb(err)
    console.log('Mac: Packaged electron. ' + buildPath)

-    var appPath = path.join(buildPath[0], config.APP_NAME + '.app')
-    var contentsPath = path.join(appPath, 'Contents')
-    var resourcesPath = path.join(contentsPath, 'Resources')
-    var infoPlistPath = path.join(contentsPath, 'Info.plist')
-    var infoPlist = plist.parse(fs.readFileSync(infoPlistPath, 'utf8'))
+    const appPath = path.join(buildPath[0], config.APP_NAME + '.app')
+    const contentsPath = path.join(appPath, 'Contents')
+    const resourcesPath = path.join(contentsPath, 'Resources')
+    const infoPlistPath = path.join(contentsPath, 'Info.plist')
+    const infoPlist = plist.parse(fs.readFileSync(infoPlistPath, 'utf8'))

    infoPlist.CFBundleDocumentTypes = [
      {
@@ -261,7 +268,7 @@ function buildDarwin (cb) {
    }

    function signApp (cb) {
-      var sign = require('electron-osx-sign')
+      const sign = require('electron-osx-sign')

      /*
       * Sign the app with Apple Developer ID certificates. We sign the app for 2 reasons:
@@ -276,7 +283,7 @@ function buildDarwin (cb) {
       *   - Xcode Command Line Tools (xcode-select --install)
       *   - Membership in the Apple Developer Program
       */
-      var signOpts = {
+      const signOpts = {
        app: appPath,
        platform: 'darwin',
        verbose: true
@@ -302,8 +309,8 @@ function buildDarwin (cb) {
      // Create .zip file (used by the auto-updater)
      console.log('Mac: Creating zip...')

-      var inPath = path.join(buildPath[0], config.APP_NAME + '.app')
-      var outPath = path.join(DIST_PATH, BUILD_NAME + '-darwin.zip')
+      const inPath = path.join(buildPath[0], config.APP_NAME + '.app')
+      const outPath = path.join(DIST_PATH, BUILD_NAME + '-darwin.zip')
      zip.zipSync(inPath, outPath)

      console.log('Mac: Created zip.')
@@ -312,13 +319,13 @@ function buildDarwin (cb) {
    function packageDmg (cb) {
      console.log('Mac: Creating dmg...')

-      var appDmg = require('appdmg')
+      const appDmg = require('appdmg')

-      var targetPath = path.join(DIST_PATH, BUILD_NAME + '.dmg')
+      const targetPath = path.join(DIST_PATH, BUILD_NAME + '.dmg')
      rimraf.sync(targetPath)

      // Create a .dmg (Mac disk image) file, for easy user installation.
-      var dmgOpts = {
+      const dmgOpts = {
        basepath: config.ROOT_PATH,
        target: targetPath,
        specification: {
@@ -339,7 +346,7 @@ function buildDarwin (cb) {
        }
      }

-      var dmg = appDmg(dmgOpts)
+      const dmg = appDmg(dmgOpts)
      dmg.once('error', cb)
      dmg.on('progress', function (info) {
        if (info.type === 'step-begin') console.log(info.title + '...')
@@ -353,7 +360,7 @@ function buildDarwin (cb) {
 }

 function buildWin32 (cb) {
-  var installer = require('electron-winstaller')
+  const installer = require('electron-winstaller')
  console.log('Windows: Packaging electron...')

  /*
@@ -361,7 +368,7 @@ function buildWin32 (cb) {
   *   - Windows Authenticode private key and cert (authenticode.p12)
   *   - Windows Authenticode password file (authenticode.txt)
   */
-  var CERT_PATH
+  let CERT_PATH
  try {
    fs.accessSync('D:')
    CERT_PATH = 'D:'
@@ -373,12 +380,12 @@ function buildWin32 (cb) {
    if (err) return cb(err)
    console.log('Windows: Packaged electron. ' + buildPath)

-    var signWithParams
+    let signWithParams
    if (process.platform === 'win32') {
      if (argv.sign) {
-        var certificateFile = path.join(CERT_PATH, 'authenticode.p12')
-        var certificatePassword = fs.readFileSync(path.join(CERT_PATH, 'authenticode.txt'), 'utf8')
-        var timestampServer = 'http://timestamp.comodoca.com'
+        const certificateFile = path.join(CERT_PATH, 'authenticode.p12')
+        const certificatePassword = fs.readFileSync(path.join(CERT_PATH, 'authenticode.txt'), 'utf8')
+        const timestampServer = 'http://timestamp.comodoca.com'
        signWithParams = `/a /f "${certificateFile}" /p "${certificatePassword}" /tr "${timestampServer}" /td sha256`
      } else {
        printWarning()
@@ -387,20 +394,26 @@ function buildWin32 (cb) {
      printWarning()
    }

-    var tasks = []
-    if (argv.package === 'exe' || argv.package === 'all') {
-      tasks.push((cb) => packageInstaller(cb))
-    }
-    if (argv.package === 'portable' || argv.package === 'all') {
-      tasks.push((cb) => packagePortable(cb))
-    }
+    const tasks = []
+    buildPath.forEach(function (filesPath) {
+      const destArch = filesPath.split('-').pop()
+
+      if (argv.package === 'exe' || argv.package === 'all') {
+        tasks.push((cb) => packageInstaller(filesPath, destArch, cb))
+      }
+      if (argv.package === 'portable' || argv.package === 'all') {
+        tasks.push((cb) => packagePortable(filesPath, destArch, cb))
+      }
+    })
    series(tasks, cb)

-    function packageInstaller (cb) {
-      console.log('Windows: Creating installer...')
+    function packageInstaller (filesPath, destArch, cb) {
+      console.log(`Windows: Creating ${destArch} installer...`)
+
+      const archStr = destArch === 'ia32' ? '-ia32' : ''

      installer.createWindowsInstaller({
-        appDirectory: buildPath[0],
+        appDirectory: filesPath,
        authors: config.APP_TEAM,
        description: config.APP_NAME,
        exe: config.APP_NAME + '.exe',
@@ -410,8 +423,26 @@ function buildWin32 (cb) {
        noMsi: true,
        outputDirectory: DIST_PATH,
        productName: config.APP_NAME,
-        remoteReleases: config.GITHUB_URL,
-        setupExe: config.APP_NAME + 'Setup-v' + config.APP_VERSION + '.exe',
+        /**
+         * Only create delta updates for the Windows x64 build because 90% of our
+         * users have Windows x64 and the delta files take a *very* long time to
+         * generate. Also, the ia32 files on GitHub have non-standard Squirrel
+         * names (i.e. RELEASES-ia32 instead of RELEASES) and so Squirrel won't
+         * find them unless we proxy the requests.
+         */
+        // TODO: Re-enable Windows 64-bit delta updates when we confirm that they
+        //       work correctly in the presence of the "ia32" .nupkg files. I
+        //       (feross) noticed them listed in the 64-bit RELEASES file and
+        //       manually edited them out for the v0.17 release. Shipping only
+        //       full updates for now will work fine, with no ill-effects.
+        // remoteReleases: destArch === 'x64'
+        //   ? config.GITHUB_URL
+        //   : undefined,
+        /**
+         * If you hit a "GitHub API rate limit exceeded" error, set this token!
+         */
+        // remoteToken: process.env.WEBTORRENT_GITHUB_API_TOKEN,
+        setupExe: config.APP_NAME + 'Setup-v' + config.APP_VERSION + archStr + '.exe',
        setupIcon: config.APP_ICON + '.ico',
        signWithParams: signWithParams,
        title: config.APP_NAME,
@@ -419,23 +450,71 @@ function buildWin32 (cb) {
        version: pkg.version
      })
      .then(function () {
-        console.log('Windows: Created installer.')
+        console.log(`Windows: Created ${destArch} installer.`)
+
+        /**
+         * Delete extraneous Squirrel files (i.e. *.nupkg delta files for older
+         * versions of the app)
+         */
+        fs.readdirSync(DIST_PATH)
+          .filter((name) => name.endsWith('.nupkg') && !name.includes(pkg.version))
+          .forEach((filename) => {
+            fs.unlinkSync(path.join(DIST_PATH, filename))
+          })
+
+        if (destArch === 'ia32') {
+          console.log('Windows: Renaming ia32 installer files...')
+
+          // RELEASES -> RELEASES-ia32
+          const relPath = path.join(DIST_PATH, 'RELEASES-ia32')
+          fs.renameSync(
+            path.join(DIST_PATH, 'RELEASES'),
+            relPath
+          )
+
+          // WebTorrent-vX.X.X-full.nupkg -> WebTorrent-vX.X.X-ia32-full.nupkg
+          fs.renameSync(
+            path.join(DIST_PATH, `${config.APP_NAME}-${config.APP_VERSION}-full.nupkg`),
+            path.join(DIST_PATH, `${config.APP_NAME}-${config.APP_VERSION}-ia32-full.nupkg`)
+          )
+
+          // Change file name inside RELEASES-ia32 to match renamed file
+          const relContent = fs.readFileSync(relPath, 'utf8')
+          const relContent32 = relContent.replace('full.nupkg', 'ia32-full.nupkg')
+          fs.writeFileSync(relPath, relContent32)
+
+          if (relContent === relContent32) {
+            // Sanity check
+            throw new Error('Fixing RELEASES-ia32 failed. Replacement did not modify the file.')
+          }
+
+          console.log('Windows: Renamed ia32 installer files.')
+        }
+
        cb(null)
      })
      .catch(cb)
    }

-    function packagePortable (cb) {
-      console.log('Windows: Creating portable app...')
+    function packagePortable (filesPath, destArch, cb) {
+      console.log(`Windows: Creating ${destArch} portable app...`)

-      var portablePath = path.join(buildPath[0], 'Portable Settings')
+      const portablePath = path.join(filesPath, 'Portable Settings')
      mkdirp.sync(portablePath)

-      var inPath = path.join(DIST_PATH, path.basename(buildPath[0]))
-      var outPath = path.join(DIST_PATH, BUILD_NAME + '-win.zip')
+      const downloadsPath = path.join(portablePath, 'Downloads')
+      mkdirp.sync(downloadsPath)
+
+      const tempPath = path.join(portablePath, 'Temp')
+      mkdirp.sync(tempPath)
+
+      const archStr = destArch === 'ia32' ? '-ia32' : ''
+
+      const inPath = path.join(DIST_PATH, path.basename(filesPath))
+      const outPath = path.join(DIST_PATH, BUILD_NAME + '-win' + archStr + '.zip')
      zip.zipSync(inPath, outPath)

-      console.log('Windows: Created portable app.')
+      console.log(`Windows: Created ${destArch} portable app.`)
      cb(null)
    }
  })
@@ -447,9 +526,9 @@ function buildLinux (cb) {
    if (err) return cb(err)
    console.log('Linux: Packaged electron. ' + buildPath)

-    var tasks = []
+    const tasks = []
    buildPath.forEach(function (filesPath) {
-      var destArch = filesPath.split('-').pop()
+      const destArch = filesPath.split('-').pop()

      if (argv.package === 'deb' || argv.package === 'all') {
        tasks.push((cb) => packageDeb(filesPath, destArch, cb))
@@ -465,8 +544,8 @@ function buildLinux (cb) {
    // Create .deb file for Debian-based platforms
    console.log(`Linux: Creating ${destArch} deb...`)

-    var deb = require('nobin-debian-installer')()
-    var destPath = path.join('/opt', pkg.name)
+    const deb = require('nobin-debian-installer')()
+    const destPath = path.join('/opt', pkg.name)

    deb.pack({
      package: pkg,
@@ -500,8 +579,10 @@ function buildLinux (cb) {
    // Create .zip file for Linux
    console.log(`Linux: Creating ${destArch} zip...`)

-    var inPath = path.join(DIST_PATH, path.basename(filesPath))
-    var outPath = path.join(DIST_PATH, BUILD_NAME + '-linux-' + destArch + '.zip')
+    const archStr = destArch === 'ia32' ? '-ia32' : ''
+
+    const inPath = path.join(DIST_PATH, path.basename(filesPath))
+    const outPath = path.join(DIST_PATH, BUILD_NAME + '-linux' + archStr + '.zip')
    zip.zipSync(inPath, outPath)

    console.log(`Linux: Created ${destArch} zip.`)
--- a/bin/release-_post.sh
+++ b/bin/release-_post.sh
@@ -1,10 +0,0 @@
-#!/bin/sh
-set -e
-
-npm run update-authors
-git diff --exit-code
-npm run package -- --sign
-git push
-git push --tags
-npm publish
-./node_modules/.bin/gh-release
--- a/bin/release-_pre.sh
+++ b/bin/release-_pre.sh
@@ -1,8 +0,0 @@
-#!/bin/sh
-set -e
-
-git pull
-rm -rf node_modules/
-npm install
-npm dedupe
-npm test
--- a/bin/release-major.sh
+++ b/bin/release-major.sh
@@ -1,7 +0,0 @@
-#!/bin/sh
-set -e
-BIN=`dirname $0`
-
-$BIN/release-_pre.sh
-npm version major
-$BIN/release-_post.sh
--- a/bin/release-minor.sh
+++ b/bin/release-minor.sh
@@ -1,7 +0,0 @@
-#!/bin/sh
-set -e
-BIN=`dirname $0`
-
-$BIN/release-_pre.sh
-npm version minor
-$BIN/release-_post.sh
--- a/bin/release-patch.sh
+++ b/bin/release-patch.sh
@@ -1,7 +0,0 @@
-#!/bin/sh
-set -e
-BIN=`dirname $0`
-
-$BIN/release-_pre.sh
-npm version patch
-$BIN/release-_post.sh
--- a/package.json
+++ b/package.json
@@ -1,40 +1,44 @@
 {
  "name": "webtorrent-desktop",
  "description": "WebTorrent, the streaming torrent client. For Mac, Windows, and Linux.",
-  "version": "0.12.0",
+  "version": "0.18.0",
  "author": {
    "name": "WebTorrent, LLC",
    "email": "feross@webtorrent.io",
    "url": "https://webtorrent.io"
  },
-  "bin": {
-    "webtorrent-desktop": "./bin/cmd.js"
-  },
  "bugs": {
    "url": "https://github.com/feross/webtorrent-desktop/issues"
  },
  "dependencies": {
    "airplayer": "^2.0.0",
    "application-config": "^1.0.0",
+    "arch": "^2.0.0",
+    "auto-launch": "^4.0.1",
    "bitfield": "^1.0.2",
+    "capture-frame": "^1.0.0",
    "chromecasts": "^1.8.0",
+    "cp-file": "^4.0.1",
    "create-torrent": "^3.24.5",
+    "debounce": "^1.0.0",
    "deep-equal": "^1.0.1",
    "dlnacasts": "^0.1.0",
    "drag-drop": "^2.12.1",
-    "electron": "1.3.3",
-    "fs-extra": "^0.30.0",
+    "es6-error": "^4.0.0",
+    "fn-getter": "^1.0.0",
    "iso-639-1": "^1.2.1",
    "languagedetect": "^1.1.1",
    "location-history": "^1.0.0",
-    "material-ui": "^0.15.4",
+    "material-ui": "^0.17.0",
+    "mkdirp": "^0.5.1",
    "musicmetadata": "^2.0.2",
    "network-address": "^1.1.0",
    "parse-torrent": "^5.7.3",
    "prettier-bytes": "^1.0.1",
-    "react": "^15.2.1",
-    "react-dom": "^15.2.1",
-    "react-tap-event-plugin": "^1.0.0",
+    "react": "^15.4.2",
+    "react-dom": "^15.4.2",
+    "react-tap-event-plugin": "^2.0.1",
+    "rimraf": "^2.5.2",
    "run-parallel": "^1.1.6",
    "semver": "^5.1.0",
    "simple-concat": "^1.0.0",
@@ -46,25 +50,25 @@
    "zero-fill": "^2.2.3"
  },
  "devDependencies": {
-    "babel-cli": "^6.11.4",
-    "babel-plugin-syntax-jsx": "^6.13.0",
-    "babel-plugin-transform-es2015-destructuring": "^6.9.0",
-    "babel-plugin-transform-object-rest-spread": "^6.8.0",
-    "babel-plugin-transform-react-jsx": "^6.8.0",
+    "buble": "^0.15.2",
    "cross-zip": "^2.0.1",
-    "electron-osx-sign": "^0.3.0",
-    "electron-packager": "^7.0.0",
-    "electron-winstaller": "^2.3.0",
+    "depcheck": "^0.6.4",
+    "electron": "1.6.0",
+    "electron-osx-sign": "0.4.3",
+    "electron-packager": "~8.5.1",
+    "electron-winstaller": "~2.5.2",
    "gh-release": "^2.0.3",
    "minimist": "^1.2.0",
-    "mkdirp": "^0.5.1",
-    "nobin-debian-installer": "^0.0.10",
+    "nobin-debian-installer": "0.0.10",
    "nodemon": "^1.10.2",
    "open": "0.0.5",
    "plist": "^2.0.1",
-    "rimraf": "^2.5.2",
+    "pngjs": "^3.0.0",
    "run-series": "^1.1.4",
-    "standard": "*"
+    "spectron": "^3.3.0",
+    "standard": "*",
+    "tape": "^4.6.0",
+    "walk-sync": "^0.3.1"
  },
  "engines": {
    "node": ">=4.0.0"
@@ -85,20 +89,23 @@
  "optionalDependencies": {
    "appdmg": "^0.4.3"
  },
+  "private": true,
  "productName": "WebTorrent",
  "repository": {
    "type": "git",
    "url": "git://github.com/feross/webtorrent-desktop.git"
  },
  "scripts": {
-    "build": "babel --quiet src --out-dir build",
+    "build": "buble src --output build",
    "clean": "node ./bin/clean.js",
+    "gh-release": "gh-release",
    "open-config": "node ./bin/open-config.js",
    "package": "node ./bin/package.js",
    "prepublish": "npm run build",
    "start": "npm run build && electron .",
-    "test": "standard && node ./bin/check-deps.js",
+    "test": "standard && depcheck --ignores=buble,nodemon,gh-release --ignore-dirs=build,dist && node ./bin/extra-lint.js",
+    "test-integration": "npm run build && node ./test",
    "update-authors": "./bin/update-authors.sh",
-    "watch": "nodemon --exec 'npm run start' --ext js,pug,css"
+    "watch": "nodemon --exec \"npm run start\" --ext js,css --ignore build/ --ignore dist/"
  }
 }
--- a/src/.babelrc
+++ b/src/.babelrc
@@ -1,8 +0,0 @@
-{
-  "plugins": [
-    "syntax-jsx",
-    "transform-es2015-destructuring",
-    "transform-object-rest-spread",
-    "transform-react-jsx"
-  ]
-}
--- a/src/config.js
+++ b/src/config.js
@@ -1,12 +1,21 @@
-var appConfig = require('application-config')('WebTorrent')
-var fs = require('fs')
-var path = require('path')
+const appConfig = require('application-config')('WebTorrent')
+const path = require('path')
+const electron = require('electron')
+const arch = require('arch')

-var APP_NAME = 'WebTorrent'
-var APP_TEAM = 'WebTorrent, LLC'
-var APP_VERSION = require('../package.json').version
+const APP_NAME = 'WebTorrent'
+const APP_TEAM = 'WebTorrent, LLC'
+const APP_VERSION = require('../package.json').version

-var PORTABLE_PATH = path.join(path.dirname(process.execPath), 'Portable Settings')
+const IS_TEST = isTest()
+const PORTABLE_PATH = IS_TEST
+  ? path.join(process.platform === 'win32' ? 'C:\\Windows\\Temp' : '/tmp', 'WebTorrentTest')
+  : path.join(path.dirname(process.execPath), 'Portable Settings')
+const IS_PRODUCTION = isProduction()
+const IS_PORTABLE = isPortable()
+
+const UI_HEADER_HEIGHT = 38
+const UI_TORRENT_HEIGHT = 100

 module.exports = {
  ANNOUNCEMENT_URL: 'https://webtorrent.io/desktop/announcement',
@@ -14,7 +23,7 @@ module.exports = {
  CRASH_REPORT_URL: 'https://webtorrent.io/desktop/crash-report',
  TELEMETRY_URL: 'https://webtorrent.io/desktop/telemetry',

-  APP_COPYRIGHT: 'Copyright © 2014-2016 ' + APP_TEAM,
+  APP_COPYRIGHT: 'Copyright © 2014-2017 ' + APP_TEAM,
  APP_FILE_ICON: path.join(__dirname, '..', 'static', 'WebTorrentFile'),
  APP_ICON: path.join(__dirname, '..', 'static', 'WebTorrent'),
  APP_NAME: APP_NAME,
@@ -26,27 +35,32 @@ module.exports = {

  DEFAULT_TORRENTS: [
    {
+      testID: 'bbb',
      name: 'Big Buck Bunny',
      posterFileName: 'bigBuckBunny.jpg',
      torrentFileName: 'bigBuckBunny.torrent'
    },
    {
+      testID: 'cosmos',
      name: 'Cosmos Laundromat (Preview)',
      posterFileName: 'cosmosLaundromat.jpg',
      torrentFileName: 'cosmosLaundromat.torrent'
    },
    {
+      testID: 'sintel',
      name: 'Sintel',
      posterFileName: 'sintel.jpg',
      torrentFileName: 'sintel.torrent'
    },
    {
+      testID: 'tears',
      name: 'Tears of Steel',
      posterFileName: 'tearsOfSteel.jpg',
      torrentFileName: 'tearsOfSteel.torrent'
    },
    {
-      name: 'The WIRED CD - Rip. Sample. Mash. Share.',
+      testID: 'wired',
+      name: 'The WIRED CD - Rip. Sample. Mash. Share',
      posterFileName: 'wiredCd.jpg',
      torrentFileName: 'wiredCd.torrent'
    }
@@ -62,8 +76,11 @@ module.exports = {

  HOME_PAGE_URL: 'https://webtorrent.io',

-  IS_PORTABLE: isPortable(),
-  IS_PRODUCTION: isProduction(),
+  IS_PORTABLE: IS_PORTABLE,
+  IS_PRODUCTION: IS_PRODUCTION,
+  IS_TEST: IS_TEST,
+
+  OS_SYSARCH: arch() === 'x64' ? 'x64' : 'ia32',

  POSTER_PATH: path.join(getConfigPath(), 'Posters'),
  ROOT_PATH: path.join(__dirname, '..'),
@@ -74,12 +91,19 @@ module.exports = {
  WINDOW_MAIN: 'file://' + path.join(__dirname, '..', 'static', 'main.html'),
  WINDOW_WEBTORRENT: 'file://' + path.join(__dirname, '..', 'static', 'webtorrent.html'),

-  WINDOW_MIN_HEIGHT: 38 + (120 * 2), // header height + 2 torrents
-  WINDOW_MIN_WIDTH: 425
+  WINDOW_INITIAL_BOUNDS: {
+    width: 500,
+    height: UI_HEADER_HEIGHT + (UI_TORRENT_HEIGHT * 6) // header + 6 torrents
+  },
+  WINDOW_MIN_HEIGHT: UI_HEADER_HEIGHT + (UI_TORRENT_HEIGHT * 2), // header + 2 torrents
+  WINDOW_MIN_WIDTH: 425,
+
+  UI_HEADER_HEIGHT: UI_HEADER_HEIGHT,
+  UI_TORRENT_HEIGHT: UI_TORRENT_HEIGHT
 }

 function getConfigPath () {
-  if (isPortable()) {
+  if (IS_PORTABLE) {
    return PORTABLE_PATH
  } else {
    return path.dirname(appConfig.filePath)
@@ -87,24 +111,47 @@ function getConfigPath () {
 }

 function getDefaultDownloadPath () {
-  if (!process || !process.type) {
-    return ''
-  }
-
-  if (isPortable()) {
+  if (IS_PORTABLE) {
    return path.join(getConfigPath(), 'Downloads')
+  } else {
+    return getPath('downloads')
  }
+}

-  var electron = require('electron')
+function getPath (key) {
+  if (!process.versions.electron) {
+    // Node.js process
+    return ''
+  } else if (process.type === 'renderer') {
+    // Electron renderer process
+    return electron.remote.app.getPath(key)
+  } else {
+    // Electron main process
+    return electron.app.getPath(key)
+  }
+}

-  return process.type === 'renderer'
-    ? electron.remote.app.getPath('downloads')
-    : electron.app.getPath('downloads')
+function isTest () {
+  return process.env.NODE_ENV === 'test'
 }

 function isPortable () {
+  if (IS_TEST) {
+    return true
+  }
+
+  if (process.platform !== 'win32' || !IS_PRODUCTION) {
+    // Fast path: Non-Windows platforms should not check for path on disk
+    return false
+  }
+
+  const fs = require('fs')
+
  try {
-    return process.platform === 'win32' && isProduction() && !!fs.statSync(PORTABLE_PATH)
+    // This line throws if the "Portable Settings" folder does not exist, and does
+    // nothing otherwise.
+    fs.accessSync(PORTABLE_PATH, fs.constants.R_OK | fs.constants.W_OK)
+    return true
  } catch (err) {
    return false
  }
@@ -112,6 +159,7 @@ function isPortable () {

 function isProduction () {
  if (!process.versions.electron) {
+    // Node.js process
    return false
  }
  if (process.platform === 'darwin') {
--- a/src/crash-reporter.js
+++ b/src/crash-reporter.js
@@ -2,10 +2,10 @@ module.exports = {
  init
 }

-var config = require('./config')
-var electron = require('electron')
-
 function init () {
+  const config = require('./config')
+  const electron = require('electron')
+
  electron.crashReporter.start({
    companyName: config.APP_NAME,
    productName: config.APP_NAME,
--- a/src/main/announcement.js
+++ b/src/main/announcement.js
@@ -2,12 +2,12 @@ module.exports = {
  init
 }

-var electron = require('electron')
+const electron = require('electron')

-var config = require('../config')
-var log = require('./log')
+const config = require('../config')
+const log = require('./log')

-var ANNOUNCEMENT_URL = config.ANNOUNCEMENT_URL +
+const ANNOUNCEMENT_URL = config.ANNOUNCEMENT_URL +
  '?version=' + config.APP_VERSION +
  '&platform=' + process.platform

@@ -26,7 +26,7 @@ var ANNOUNCEMENT_URL = config.ANNOUNCEMENT_URL +
 *   }
 */
 function init () {
-  var get = require('simple-get')
+  const get = require('simple-get')
  get.concat(ANNOUNCEMENT_URL, onResponse)
 }

--- a/src/main/dialog.js
+++ b/src/main/dialog.js
@@ -6,10 +6,10 @@ module.exports = {
  openFiles
 }

-var electron = require('electron')
+const electron = require('electron')

-var log = require('./log')
-var windows = require('./windows')
+const log = require('./log')
+const windows = require('./windows')

 /**
 * Show open dialog to create a single-file torrent.
@@ -17,16 +17,11 @@ var windows = require('./windows')
 function openSeedFile () {
  if (!windows.main.win) return
  log('openSeedFile')
-  var opts = {
+  const opts = {
    title: 'Select a file for the torrent.',
    properties: [ 'openFile' ]
  }
-  setTitle(opts.title)
-  electron.dialog.showOpenDialog(windows.main.win, opts, function (selectedPaths) {
-    resetTitle()
-    if (!Array.isArray(selectedPaths)) return
-    windows.main.dispatch('showCreateTorrent', selectedPaths)
-  })
+  showOpenSeed(opts)
 }

 /*
@@ -37,7 +32,7 @@ function openSeedFile () {
 function openSeedDirectory () {
  if (!windows.main.win) return
  log('openSeedDirectory')
-  var opts = process.platform === 'darwin'
+  const opts = process.platform === 'darwin'
    ? {
      title: 'Select a file or folder for the torrent.',
      properties: [ 'openFile', 'openDirectory' ]
@@ -46,12 +41,7 @@ function openSeedDirectory () {
      title: 'Select a folder for the torrent.',
      properties: [ 'openDirectory' ]
    }
-  setTitle(opts.title)
-  electron.dialog.showOpenDialog(windows.main.win, opts, function (selectedPaths) {
-    resetTitle()
-    if (!Array.isArray(selectedPaths)) return
-    windows.main.dispatch('showCreateTorrent', selectedPaths)
-  })
+  showOpenSeed(opts)
 }

 /*
@@ -61,7 +51,7 @@ function openSeedDirectory () {
 function openFiles () {
  if (!windows.main.win) return
  log('openFiles')
-  var opts = process.platform === 'darwin'
+  const opts = process.platform === 'darwin'
    ? {
      title: 'Select a file or folder to add.',
      properties: [ 'openFile', 'openDirectory' ]
@@ -84,7 +74,7 @@ function openFiles () {
 function openTorrentFile () {
  if (!windows.main.win) return
  log('openTorrentFile')
-  var opts = {
+  const opts = {
    title: 'Select a .torrent file.',
    filters: [{ name: 'Torrent Files', extensions: ['torrent'] }],
    properties: [ 'openFile', 'multiSelections' ]
@@ -119,3 +109,16 @@ function setTitle (title) {
 function resetTitle () {
  windows.main.dispatch('resetTitle')
 }
+
+/**
+ * Pops up an Open File dialog with the given options.
+ * After the user selects files / folders, shows the Create Torrent page.
+ */
+function showOpenSeed (opts) {
+  setTitle(opts.title)
+  electron.dialog.showOpenDialog(windows.main.win, opts, function (selectedPaths) {
+    resetTitle()
+    if (!Array.isArray(selectedPaths)) return
+    windows.main.dispatch('showCreateTorrent', selectedPaths)
+  })
+}
--- a/src/main/dock.js
+++ b/src/main/dock.js
@@ -4,19 +4,17 @@ module.exports = {
  setBadge
 }

-var electron = require('electron')
+const {app, Menu} = require('electron')

-var app = electron.app
-
-var dialog = require('./dialog')
-var log = require('./log')
+const dialog = require('./dialog')
+const log = require('./log')

 /**
 * Add a right-click menu to the dock icon. (Mac)
 */
 function init () {
  if (!app.dock) return
-  var menu = electron.Menu.buildFromTemplate(getMenuTemplate())
+  const menu = Menu.buildFromTemplate(getMenuTemplate())
  app.dock.setMenu(menu)
 }

@@ -33,8 +31,11 @@ function downloadFinished (path) {
 * Display a counter badge for the app. (Mac, Linux)
 */
 function setBadge (count) {
-  log(`setBadge: ${count}`)
-  app.setBadgeCount(Number(count))
+  if (process.platform === 'darwin' ||
+      (process.platform === 'linux' && app.isUnityRunning())) {
+    log(`setBadge: ${count}`)
+    app.setBadgeCount(Number(count))
+  }
 }

 function getMenuTemplate () {
--- a/src/main/external-player.js
+++ b/src/main/external-player.js
@@ -4,29 +4,36 @@ module.exports = {
  checkInstall
 }

-var cp = require('child_process')
-var vlcCommand = require('vlc-command')
+const cp = require('child_process')
+const path = require('path')
+const vlcCommand = require('vlc-command')

-var log = require('./log')
-var windows = require('./windows')
+const log = require('./log')
+const windows = require('./windows')

 // holds a ChildProcess while we're playing a video in an external player, null otherwise
-var proc
+let proc = null

-function checkInstall (path, cb) {
+function checkInstall (playerPath, cb) {
  // check for VLC if external player has not been specified by the user
  // otherwise assume the player is installed
-  if (path == null) return vlcCommand((err) => cb(!err))
-  process.nextTick(() => cb(true))
+  if (playerPath == null) return vlcCommand(cb)
+  process.nextTick(() => cb(null))
 }

-function spawn (path, url, title) {
-  if (path != null) return spawnExternal(path, [url])
+function spawn (playerPath, url, title) {
+  if (playerPath != null) return spawnExternal(playerPath, [url])

  // Try to find and use VLC if external player is not specified
  vlcCommand(function (err, vlcPath) {
    if (err) return windows.main.dispatch('externalPlayerNotFound')
-    var args = ['--play-and-exit', '--video-on-top', '--quiet', `--meta-title=${JSON.stringify(title)}`, url]
+    const args = [
+      '--play-and-exit',
+      '--video-on-top',
+      '--quiet',
+      `--meta-title=${JSON.stringify(title)}`,
+      url
+    ]
    spawnExternal(vlcPath, args)
  })
 }
@@ -38,13 +45,18 @@ function kill () {
  proc = null
 }

-function spawnExternal (path, args) {
-  log('Running external media player:', path + ' ' + args.join(' '))
+function spawnExternal (playerPath, args) {
+  log('Running external media player:', playerPath + ' ' + args.join(' '))

-  proc = cp.spawn(path, args, {stdio: 'ignore'})
+  if (process.platform === 'darwin' && path.extname(playerPath) === '.app') {
+    // Mac: Use executable in packaged .app bundle
+    playerPath += '/Contents/MacOS/' + path.basename(playerPath, '.app')
+  }
+
+  proc = cp.spawn(playerPath, args, {stdio: 'ignore'})

  // If it works, close the modal after a second
-  var closeModalTimeout = setTimeout(() =>
+  const closeModalTimeout = setTimeout(() =>
    windows.main.dispatch('exitModal'), 1000)

  proc.on('close', function (code) {
--- a/src/main/handlers.js
+++ b/src/main/handlers.js
@@ -3,8 +3,8 @@ module.exports = {
  uninstall
 }

-var config = require('../config')
-var path = require('path')
+const config = require('../config')
+const path = require('path')

 function install () {
  if (process.platform === 'darwin') {
@@ -31,8 +31,8 @@ function uninstall () {
 }

 function installDarwin () {
-  var electron = require('electron')
-  var app = electron.app
+  const electron = require('electron')
+  const app = electron.app

  // On Mac, only protocols that are listed in `Info.plist` can be set as the
  // default handler at runtime.
@@ -44,18 +44,18 @@ function installDarwin () {

 function uninstallDarwin () {}

-var EXEC_COMMAND = [ process.execPath ]
+const EXEC_COMMAND = [ process.execPath ]

 if (!config.IS_PRODUCTION) {
  EXEC_COMMAND.push(config.ROOT_PATH)
 }

 function installWin32 () {
-  var Registry = require('winreg')
+  const Registry = require('winreg')

-  var log = require('./log')
+  const log = require('./log')

-  var iconPath = path.join(
+  const iconPath = path.join(
    process.resourcesPath, 'app.asar.unpacked', 'static', 'WebTorrentFile.ico'
  )
  registerProtocolHandlerWin32(
@@ -100,7 +100,7 @@ function installWin32 () {
   */

  function registerProtocolHandlerWin32 (protocol, name, icon, command) {
-    var protocolKey = new Registry({
+    const protocolKey = new Registry({
      hive: Registry.HKCU, // HKEY_CURRENT_USER
      key: '\\Software\\Classes\\' + protocol
    })
@@ -120,7 +120,7 @@ function installWin32 () {
    function setIcon (err) {
      if (err) log.error(err.message)

-      var iconKey = new Registry({
+      const iconKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + protocol + '\\DefaultIcon'
      })
@@ -130,7 +130,7 @@ function installWin32 () {
    function setCommand (err) {
      if (err) log.error(err.message)

-      var commandKey = new Registry({
+      const commandKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + protocol + '\\shell\\open\\command'
      })
@@ -161,7 +161,7 @@ function installWin32 () {
    setExt()

    function setExt () {
-      var extKey = new Registry({
+      const extKey = new Registry({
        hive: Registry.HKCU, // HKEY_CURRENT_USER
        key: '\\Software\\Classes\\' + ext
      })
@@ -171,7 +171,7 @@ function installWin32 () {
    function setId (err) {
      if (err) log.error(err.message)

-      var idKey = new Registry({
+      const idKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + id
      })
@@ -181,7 +181,7 @@ function installWin32 () {
    function setIcon (err) {
      if (err) log.error(err.message)

-      var iconKey = new Registry({
+      const iconKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + id + '\\DefaultIcon'
      })
@@ -191,7 +191,7 @@ function installWin32 () {
    function setCommand (err) {
      if (err) log.error(err.message)

-      var commandKey = new Registry({
+      const commandKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + id + '\\shell\\open\\command'
      })
@@ -205,7 +205,7 @@ function installWin32 () {
 }

 function uninstallWin32 () {
-  var Registry = require('winreg')
+  const Registry = require('winreg')

  unregisterProtocolHandlerWin32('magnet', EXEC_COMMAND)
  unregisterProtocolHandlerWin32('stream-magnet', EXEC_COMMAND)
@@ -215,7 +215,7 @@ function uninstallWin32 () {
    getCommand()

    function getCommand () {
-      var commandKey = new Registry({
+      const commandKey = new Registry({
        hive: Registry.HKCU, // HKEY_CURRENT_USER
        key: '\\Software\\Classes\\' + protocol + '\\shell\\open\\command'
      })
@@ -227,7 +227,7 @@ function uninstallWin32 () {
    }

    function destroyProtocol () {
-      var protocolKey = new Registry({
+      const protocolKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + protocol
      })
@@ -239,7 +239,7 @@ function uninstallWin32 () {
    eraseId()

    function eraseId () {
-      var idKey = new Registry({
+      const idKey = new Registry({
        hive: Registry.HKCU, // HKEY_CURRENT_USER
        key: '\\Software\\Classes\\' + id
      })
@@ -247,7 +247,7 @@ function uninstallWin32 () {
    }

    function getExt () {
-      var extKey = new Registry({
+      const extKey = new Registry({
        hive: Registry.HKCU,
        key: '\\Software\\Classes\\' + ext
      })
@@ -259,7 +259,7 @@ function uninstallWin32 () {
    }

    function destroyExt () {
-      var extKey = new Registry({
+      const extKey = new Registry({
        hive: Registry.HKCU, // HKEY_CURRENT_USER
        key: '\\Software\\Classes\\' + ext
      })
@@ -273,12 +273,12 @@ function commandToArgs (command) {
 }

 function installLinux () {
-  var fs = require('fs-extra')
-  var os = require('os')
-  var path = require('path')
+  const fs = require('fs')
+  const os = require('os')
+  const path = require('path')

-  var config = require('../config')
-  var log = require('./log')
+  const config = require('../config')
+  const log = require('./log')

  // Do not install in user dir if running on system
  if (/^\/opt/.test(process.execPath)) return
@@ -287,7 +287,7 @@ function installLinux () {
  installIconFile()

  function installDesktopFile () {
-    var templatePath = path.join(
+    const templatePath = path.join(
      config.STATIC_PATH, 'linux', 'webtorrent-desktop.desktop'
    )
    fs.readFile(templatePath, 'utf8', writeDesktopFile)
@@ -296,7 +296,7 @@ function installLinux () {
  function writeDesktopFile (err, desktopFile) {
    if (err) return log.error(err.message)

-    var appPath = config.IS_PRODUCTION
+    const appPath = config.IS_PRODUCTION
      ? path.dirname(process.execPath)
      : config.ROOT_PATH

@@ -305,7 +305,7 @@ function installLinux () {
    desktopFile = desktopFile.replace(/\$EXEC_PATH/g, EXEC_COMMAND.join(' '))
    desktopFile = desktopFile.replace(/\$TRY_EXEC_PATH/g, process.execPath)

-    var desktopFilePath = path.join(
+    const desktopFilePath = path.join(
      os.homedir(),
      '.local',
      'share',
@@ -319,47 +319,51 @@ function installLinux () {
  }

  function installIconFile () {
-    var iconStaticPath = path.join(config.STATIC_PATH, 'WebTorrent.png')
+    const iconStaticPath = path.join(config.STATIC_PATH, 'WebTorrent.png')
    fs.readFile(iconStaticPath, writeIconFile)
  }

  function writeIconFile (err, iconFile) {
    if (err) return log.error(err.message)

-    var iconFilePath = path.join(
+    const mkdirp = require('mkdirp')
+
+    const iconFilePath = path.join(
      os.homedir(),
      '.local',
      'share',
      'icons',
      'webtorrent-desktop.png'
    )
-    fs.mkdirp(path.dirname(iconFilePath))
-    fs.writeFile(iconFilePath, iconFile, function (err) {
+    mkdirp(path.dirname(iconFilePath), (err) => {
      if (err) return log.error(err.message)
+      fs.writeFile(iconFilePath, iconFile, (err) => {
+        if (err) log.error(err.message)
+      })
    })
  }
 }

 function uninstallLinux () {
-  var os = require('os')
-  var path = require('path')
-  var fs = require('fs-extra')
+  const os = require('os')
+  const path = require('path')
+  const rimraf = require('rimraf')

-  var desktopFilePath = path.join(
+  const desktopFilePath = path.join(
    os.homedir(),
    '.local',
    'share',
    'applications',
    'webtorrent-desktop.desktop'
  )
-  fs.removeSync(desktopFilePath)
+  rimraf(desktopFilePath)

-  var iconFilePath = path.join(
+  const iconFilePath = path.join(
    os.homedir(),
    '.local',
    'share',
    'icons',
    'webtorrent-desktop.png'
  )
-  fs.removeSync(iconFilePath)
+  rimraf(iconFilePath)
 }
--- a/src/main/index.js
+++ b/src/main/index.js
@@ -1,26 +1,25 @@
 console.time('init')

-var electron = require('electron')
+const electron = require('electron')
+const app = electron.app

-var app = electron.app
-var ipcMain = electron.ipcMain
+const parallel = require('run-parallel')

-var announcement = require('./announcement')
-var config = require('../config')
-var crashReporter = require('../crash-reporter')
-var dialog = require('./dialog')
-var dock = require('./dock')
-var ipc = require('./ipc')
-var log = require('./log')
-var menu = require('./menu')
-var squirrelWin32 = require('./squirrel-win32')
-var tray = require('./tray')
-var updater = require('./updater')
-var userTasks = require('./user-tasks')
-var windows = require('./windows')
+const config = require('../config')
+const crashReporter = require('../crash-reporter')
+const ipc = require('./ipc')
+const log = require('./log')
+const menu = require('./menu')
+const State = require('../renderer/lib/state')
+const windows = require('./windows')

-var shouldQuit = false
-var argv = sliceArgv(process.argv)
+let shouldQuit = false
+let argv = sliceArgv(process.argv)
+
+// Start the app without showing the main window when auto launching on login
+// (On Windows and Linux, we get a flag. On MacOS, we get special API.)
+const hidden = argv.includes('--hidden') ||
+  (process.platform === 'darwin' && app.getLoginItemSettings().wasOpenedAsHidden)

 if (config.IS_PRODUCTION) {
  // When Electron is running in production mode (packaged app), then run React
@@ -29,13 +28,16 @@ if (config.IS_PRODUCTION) {
 }

 if (process.platform === 'win32') {
+  const squirrelWin32 = require('./squirrel-win32')
  shouldQuit = squirrelWin32.handleEvent(argv[0])
  argv = argv.filter((arg) => !arg.includes('--squirrel'))
 }

-if (!shouldQuit) {
+if (!shouldQuit && !config.IS_PORTABLE) {
  // Prevent multiple instances of app from running at same time. New instances
-  // signal this instance and quit.
+  // signal this instance and quit. Note: This feature creates a lock file in
+  // %APPDATA%\Roaming\WebTorrent so we do not do it for the Portable App since
+  // we want to be "silent" as well as "portable".
  shouldQuit = app.makeSingleInstance(onAppOpen)
  if (shouldQuit) {
    app.quit()
@@ -48,27 +50,30 @@ if (!shouldQuit) {

 function init () {
  if (config.IS_PORTABLE) {
+    const path = require('path')
+    // Put all user data into the "Portable Settings" folder
    app.setPath('userData', config.CONFIG_PATH)
+    // Put Electron crash files, etc. into the "Portable Settings\Temp" folder
+    app.setPath('temp', path.join(config.CONFIG_PATH, 'Temp'))
  }

-  var isReady = false // app ready, windows can be created
+  const ipcMain = electron.ipcMain
+
+  let isReady = false // app ready, windows can be created
  app.ipcReady = false // main window has finished loading and IPC is ready
  app.isQuitting = false

-  // Open handlers must be added as early as possible
-  app.on('open-file', onOpen)
-  app.on('open-url', onOpen)
+  parallel({
+    appReady: (cb) => app.on('ready', () => cb(null)),
+    state: (cb) => State.load(cb)
+  }, onReady)

-  ipc.init()
+  function onReady (err, results) {
+    if (err) throw err

-  app.once('will-finish-launching', function () {
-    crashReporter.init()
-  })
-
-  app.on('ready', function () {
    isReady = true

-    windows.main.init()
+    windows.main.init(results.state, {hidden: hidden})
    windows.webtorrent.init()
    menu.init()

@@ -78,9 +83,18 @@ function init () {
    // Report uncaught exceptions
    process.on('uncaughtException', (err) => {
      console.error(err)
-      var error = {message: err.message, stack: err.stack}
+      const error = {message: err.message, stack: err.stack}
      windows.main.dispatch('uncaughtError', 'main', error)
    })
+  }
+
+  app.on('open-file', onOpen)
+  app.on('open-url', onOpen)
+
+  ipc.init()
+
+  app.once('will-finish-launching', function () {
+    crashReporter.init()
  })

  app.once('ipcReady', function () {
@@ -94,12 +108,12 @@ function init () {

    app.isQuitting = true
    e.preventDefault()
-    windows.main.dispatch('saveState') // try to save state on exit
-    ipcMain.once('savedState', () => app.quit())
+    windows.main.dispatch('stateSaveImmediate') // try to save state on exit
+    ipcMain.once('stateSaved', () => app.quit())
    setTimeout(() => {
      console.error('Saving state took too long. Quitting.')
      app.quit()
-    }, 2000) // quit after 2 secs, at most
+    }, 4000) // quit after 4 secs, at most
  })

  app.on('activate', function () {
@@ -108,11 +122,25 @@ function init () {
 }

 function delayedInit () {
+  if (app.isQuitting) return
+
+  const announcement = require('./announcement')
+  const dock = require('./dock')
+  const updater = require('./updater')
+
  announcement.init()
  dock.init()
-  tray.init()
  updater.init()
-  userTasks.init()
+
+  if (process.platform === 'win32') {
+    const userTasks = require('./user-tasks')
+    userTasks.init()
+  }
+
+  if (process.platform !== 'darwin') {
+    const tray = require('./tray')
+    tray.init()
+  }
 }

 function onOpen (e, torrentId) {
@@ -143,22 +171,38 @@ function onAppOpen (newArgv) {
  }
 }

+// Remove leading args.
+// Production: 1 arg, eg: /Applications/WebTorrent.app/Contents/MacOS/WebTorrent
+// Development: 2 args, eg: electron .
+// Test: 4 args, eg: electron -r .../mocks.js .
 function sliceArgv (argv) {
-  return argv.slice(config.IS_PRODUCTION ? 1 : 2)
+  return argv.slice(config.IS_PRODUCTION ? 1
+    : config.IS_TEST ? 4
+    : 2)
 }

 function processArgv (argv) {
-  var torrentIds = []
+  let torrentIds = []
  argv.forEach(function (arg) {
-    if (arg === '-n') {
-      dialog.openSeedDirectory()
-    } else if (arg === '-o') {
-      dialog.openTorrentFile()
-    } else if (arg === '-u') {
-      dialog.openTorrentAddress()
+    if (arg === '-n' || arg === '-o' || arg === '-u') {
+      // Critical path: Only load the 'dialog' package if it is needed
+      const dialog = require('./dialog')
+      if (arg === '-n') {
+        dialog.openSeedDirectory()
+      } else if (arg === '-o') {
+        dialog.openTorrentFile()
+      } else if (arg === '-u') {
+        dialog.openTorrentAddress()
+      }
+    } else if (arg === '--hidden') {
+      // Ignore hidden argument, already being handled
    } else if (arg.startsWith('-psn')) {
      // Ignore Mac launchd "process serial number" argument
      // Issue: https://github.com/feross/webtorrent-desktop/issues/214
+    } else if (arg.startsWith('--')) {
+      // Ignore Spectron flags
+    } else if (arg === 'data:,') {
+      // Ignore weird Spectron argument
    } else if (arg !== '.') {
      // Ignore '.' argument, which gets misinterpreted as a torrent id, when a
      // development copy of WebTorrent is started while a production version is
--- a/src/main/ipc.js
+++ b/src/main/ipc.js
@@ -2,27 +2,19 @@ module.exports = {
  init
 }

-var electron = require('electron')
+const electron = require('electron')

-var app = electron.app
+const app = electron.app

-var dialog = require('./dialog')
-var dock = require('./dock')
-var handlers = require('./handlers')
-var log = require('./log')
-var menu = require('./menu')
-var powerSaveBlocker = require('./power-save-blocker')
-var shell = require('./shell')
-var shortcuts = require('./shortcuts')
-var externalPlayer = require('./external-player')
-var windows = require('./windows')
-var thumbar = require('./thumbar')
+const log = require('./log')
+const menu = require('./menu')
+const windows = require('./windows')

 // Messages from the main process, to be sent once the WebTorrent process starts
-var messageQueueMainToWebTorrent = []
+const messageQueueMainToWebTorrent = []

 function init () {
-  var ipc = electron.ipcMain
+  const ipc = electron.ipcMain

  ipc.once('ipcReady', function (e) {
    app.ipcReady = true
@@ -43,40 +35,73 @@ function init () {
   * Dialog
   */

-  ipc.on('openTorrentFile', () => dialog.openTorrentFile())
-  ipc.on('openFiles', () => dialog.openFiles())
+  ipc.on('openTorrentFile', () => {
+    const dialog = require('./dialog')
+    dialog.openTorrentFile()
+  })
+  ipc.on('openFiles', () => {
+    const dialog = require('./dialog')
+    dialog.openFiles()
+  })

  /**
   * Dock
   */

-  ipc.on('setBadge', (e, ...args) => dock.setBadge(...args))
-  ipc.on('downloadFinished', (e, ...args) => dock.downloadFinished(...args))
+  ipc.on('setBadge', (e, ...args) => {
+    const dock = require('./dock')
+    dock.setBadge(...args)
+  })
+  ipc.on('downloadFinished', (e, ...args) => {
+    const dock = require('./dock')
+    dock.downloadFinished(...args)
+  })

  /**
   * Events
   */

  ipc.on('onPlayerOpen', function () {
-    menu.setPlayerOpen(true)
+    const powerSaveBlocker = require('./power-save-blocker')
+    const shortcuts = require('./shortcuts')
+    const thumbar = require('./thumbar')
+
+    menu.togglePlaybackControls(true)
    powerSaveBlocker.enable()
    shortcuts.enable()
    thumbar.enable()
  })

+  ipc.on('onPlayerUpdate', function (e, ...args) {
+    const thumbar = require('./thumbar')
+
+    menu.onPlayerUpdate(...args)
+    thumbar.onPlayerUpdate(...args)
+  })
+
  ipc.on('onPlayerClose', function () {
-    menu.setPlayerOpen(false)
+    const powerSaveBlocker = require('./power-save-blocker')
+    const shortcuts = require('./shortcuts')
+    const thumbar = require('./thumbar')
+
+    menu.togglePlaybackControls(false)
    powerSaveBlocker.disable()
    shortcuts.disable()
    thumbar.disable()
  })

  ipc.on('onPlayerPlay', function () {
+    const powerSaveBlocker = require('./power-save-blocker')
+    const thumbar = require('./thumbar')
+
    powerSaveBlocker.enable()
    thumbar.onPlayerPlay()
  })

  ipc.on('onPlayerPause', function () {
+    const powerSaveBlocker = require('./power-save-blocker')
+    const thumbar = require('./thumbar')
+
    powerSaveBlocker.disable()
    thumbar.onPlayerPause()
  })
@@ -85,23 +110,46 @@ function init () {
   * Shell
   */

-  ipc.on('openItem', (e, ...args) => shell.openItem(...args))
-  ipc.on('showItemInFolder', (e, ...args) => shell.showItemInFolder(...args))
-  ipc.on('moveItemToTrash', (e, ...args) => shell.moveItemToTrash(...args))
+  ipc.on('openItem', (e, ...args) => {
+    const shell = require('./shell')
+    shell.openItem(...args)
+  })
+  ipc.on('showItemInFolder', (e, ...args) => {
+    const shell = require('./shell')
+    shell.showItemInFolder(...args)
+  })
+  ipc.on('moveItemToTrash', (e, ...args) => {
+    const shell = require('./shell')
+    shell.moveItemToTrash(...args)
+  })

  /**
   * File handlers
   */
+
  ipc.on('setDefaultFileHandler', (e, flag) => {
+    const handlers = require('./handlers')
+
    if (flag) handlers.install()
    else handlers.uninstall()
  })

+  /**
+   * Auto start on login
+   */
+
+  ipc.on('setStartup', (e, flag) => {
+    const startup = require('./startup')
+
+    if (flag) startup.install()
+    else startup.uninstall()
+  })
+
  /**
   * Windows: Main
   */

-  var main = windows.main
+  const main = windows.main

  ipc.on('setAspectRatio', (e, ...args) => main.setAspectRatio(...args))
  ipc.on('setBounds', (e, ...args) => main.setBounds(...args))
@@ -116,16 +164,32 @@ function init () {
   */

  ipc.on('checkForExternalPlayer', function (e, path) {
-    externalPlayer.checkInstall(path, function (isInstalled) {
-      windows.main.send('checkForExternalPlayer', isInstalled)
+    const externalPlayer = require('./external-player')
+
+    externalPlayer.checkInstall(path, function (err) {
+      windows.main.send('checkForExternalPlayer', !err)
    })
  })

-  ipc.on('openExternalPlayer', (e, ...args) => externalPlayer.spawn(...args))
-  ipc.on('quitExternalPlayer', () => externalPlayer.kill())
+  ipc.on('openExternalPlayer', (e, ...args) => {
+    const externalPlayer = require('./external-player')
+    const thumbar = require('./thumbar')

-  // Capture all events
-  var oldEmit = ipc.emit
+    menu.togglePlaybackControls(false)
+    thumbar.disable()
+    externalPlayer.spawn(...args)
+  })
+
+  ipc.on('quitExternalPlayer', () => {
+    const externalPlayer = require('./external-player')
+    externalPlayer.kill()
+  })
+
+  /**
+   * Message passing
+   */
+
+  const oldEmit = ipc.emit
  ipc.emit = function (name, e, ...args) {
    // Relay messages between the main window and the WebTorrent hidden window
    if (name.startsWith('wt-') && !app.isQuitting) {
--- a/src/main/log.js
+++ b/src/main/log.js
@@ -8,10 +8,10 @@ module.exports.error = error
 * where they can be viewed in Developer Tools.
 */

-var electron = require('electron')
-var windows = require('./windows')
+const electron = require('electron')
+const windows = require('./windows')

-var app = electron.app
+const app = electron.app

 function log (...args) {
  if (app.ipcReady) {
--- a/src/main/menu.js
+++ b/src/main/menu.js
@@ -1,30 +1,31 @@
 module.exports = {
  init,
-  setPlayerOpen,
+  togglePlaybackControls,
  setWindowFocus,
  setAllowNav,
+  onPlayerUpdate,
  onToggleAlwaysOnTop,
  onToggleFullScreen
 }

-var electron = require('electron')
+const electron = require('electron')

-var app = electron.app
+const app = electron.app

-var config = require('../config')
-var dialog = require('./dialog')
-var shell = require('./shell')
-var windows = require('./windows')
+const config = require('../config')
+const windows = require('./windows')

-var menu
+let menu = null

 function init () {
  menu = electron.Menu.buildFromTemplate(getMenuTemplate())
  electron.Menu.setApplicationMenu(menu)
 }

-function setPlayerOpen (flag) {
+function togglePlaybackControls (flag) {
  getMenuItem('Play/Pause').enabled = flag
+  getMenuItem('Skip Next').enabled = flag
+  getMenuItem('Skip Previous').enabled = flag
  getMenuItem('Increase Volume').enabled = flag
  getMenuItem('Decrease Volume').enabled = flag
  getMenuItem('Step Forward').enabled = flag
@@ -32,6 +33,16 @@ function setPlayerOpen (flag) {
  getMenuItem('Increase Speed').enabled = flag
  getMenuItem('Decrease Speed').enabled = flag
  getMenuItem('Add Subtitles File...').enabled = flag
+
+  if (flag === false) {
+    getMenuItem('Skip Next').enabled = false
+    getMenuItem('Skip Previous').enabled = false
+  }
+}
+
+function onPlayerUpdate (hasNext, hasPrevious) {
+  getMenuItem('Skip Next').enabled = hasNext
+  getMenuItem('Skip Previous').enabled = hasPrevious
 }

 function setWindowFocus (flag) {
@@ -59,8 +70,8 @@ function onToggleFullScreen (flag) {
 }

 function getMenuItem (label) {
-  for (var i = 0; i < menu.items.length; i++) {
-    var menuItem = menu.items[i].submenu.items.find(function (item) {
+  for (let i = 0; i < menu.items.length; i++) {
+    const menuItem = menu.items[i].submenu.items.find(function (item) {
      return item.label === label
    })
    if (menuItem) return menuItem
@@ -68,7 +79,7 @@ function getMenuItem (label) {
 }

 function getMenuTemplate () {
-  var template = [
+  const template = [
    {
      label: 'File',
      submenu: [
@@ -77,17 +88,26 @@ function getMenuTemplate () {
            ? 'Create New Torrent...'
            : 'Create New Torrent from Folder...',
          accelerator: 'CmdOrCtrl+N',
-          click: () => dialog.openSeedDirectory()
+          click: () => {
+            const dialog = require('./dialog')
+            dialog.openSeedDirectory()
+          }
        },
        {
          label: 'Open Torrent File...',
          accelerator: 'CmdOrCtrl+O',
-          click: () => dialog.openTorrentFile()
+          click: () => {
+            const dialog = require('./dialog')
+            dialog.openTorrentFile()
+          }
        },
        {
          label: 'Open Torrent Address...',
          accelerator: 'CmdOrCtrl+U',
-          click: () => dialog.openTorrentAddress()
+          click: () => {
+            const dialog = require('./dialog')
+            dialog.openTorrentAddress()
+          }
        },
        {
          type: 'separator'
@@ -187,6 +207,21 @@ function getMenuTemplate () {
        {
          type: 'separator'
        },
+        {
+          label: 'Skip Next',
+          accelerator: 'N',
+          click: () => windows.main.dispatch('nextTrack'),
+          enabled: false
+        },
+        {
+          label: 'Skip Previous',
+          accelerator: 'P',
+          click: () => windows.main.dispatch('previousTrack'),
+          enabled: false
+        },
+        {
+          type: 'separator'
+        },
        {
          label: 'Increase Volume',
          accelerator: 'CmdOrCtrl+Up',
@@ -243,31 +278,53 @@ function getMenuTemplate () {
        }
      ]
    },
+    {
+      label: 'Transfers',
+      submenu: [
+        {
+          label: 'Pause All',
+          click: () => windows.main.dispatch('pauseAllTorrents')
+        },
+        {
+          label: 'Resume All',
+          click: () => windows.main.dispatch('resumeAllTorrents')
+        }
+      ]
+    },
    {
      label: 'Help',
      role: 'help',
      submenu: [
        {
          label: 'Learn more about ' + config.APP_NAME,
-          click: () => shell.openExternal(config.HOME_PAGE_URL)
+          click: () => {
+            const shell = require('./shell')
+            shell.openExternal(config.HOME_PAGE_URL)
+          }
        },
        {
          label: 'Contribute on GitHub',
-          click: () => shell.openExternal(config.GITHUB_URL)
+          click: () => {
+            const shell = require('./shell')
+            shell.openExternal(config.GITHUB_URL)
+          }
        },
        {
          type: 'separator'
        },
        {
          label: 'Report an Issue...',
-          click: () => shell.openExternal(config.GITHUB_URL_ISSUES)
+          click: () => {
+            const shell = require('./shell')
+            shell.openExternal(config.GITHUB_URL_ISSUES)
+          }
        }
      ]
    }
  ]

  if (process.platform === 'darwin') {
-    // Add WebTorrent app menu (Mac)
+    // WebTorrent menu (Mac)
    template.unshift({
      label: config.APP_NAME,
      submenu: [
@@ -310,8 +367,26 @@ function getMenuTemplate () {
      ]
    })

-    // Add Window menu (Mac)
-    template.splice(5, 0, {
+    // Edit menu (Mac)
+    template[2].submenu.push(
+      {
+        type: 'separator'
+      },
+      {
+        label: 'Speech',
+        submenu: [
+          {
+            role: 'startspeaking'
+          },
+          {
+            role: 'stopspeaking'
+          }
+        ]
+      }
+    )
+
+    // Window menu (Mac)
+    template.splice(6, 0, {
      role: 'window',
      submenu: [
        {
@@ -333,7 +408,10 @@ function getMenuTemplate () {
    // File menu (Windows, Linux)
    template[0].submenu.unshift({
      label: 'Create New Torrent from File...',
-      click: () => dialog.openSeedFile()
+      click: () => {
+        const dialog = require('./dialog')
+        dialog.openSeedFile()
+      }
    })

    // Edit menu (Windows, Linux)
@@ -348,7 +426,7 @@ function getMenuTemplate () {
      })

    // Help menu (Windows, Linux)
-    template[4].submenu.push(
+    template[5].submenu.push(
      {
        type: 'separator'
      },
--- a/src/main/power-save-blocker.js
+++ b/src/main/power-save-blocker.js
@@ -3,10 +3,10 @@ module.exports = {
  disable
 }

-var electron = require('electron')
-var log = require('./log')
+const electron = require('electron')
+const log = require('./log')

-var blockId = 0
+let blockId = 0

 /**
 * Block the system from entering low-power (sleep) mode or turning off the
--- a/src/main/shell.js
+++ b/src/main/shell.js
@@ -5,8 +5,8 @@ module.exports = {
  moveItemToTrash
 }

-var electron = require('electron')
-var log = require('./log')
+const electron = require('electron')
+const log = require('./log')

 /**
 * Open the given external protocol URL in the desktop’s default manner.
--- a/src/main/shortcuts.js
+++ b/src/main/shortcuts.js
@@ -3,8 +3,8 @@ module.exports = {
  enable
 }

-var electron = require('electron')
-var windows = require('./windows')
+const electron = require('electron')
+const windows = require('./windows')

 function enable () {
  // Register play/pause media key, available on some keyboards.
@@ -12,9 +12,19 @@ function enable () {
    'MediaPlayPause',
    () => windows.main.dispatch('playPause')
  )
+  electron.globalShortcut.register(
+    'MediaNextTrack',
+    () => windows.main.dispatch('nextTrack')
+  )
+  electron.globalShortcut.register(
+    'MediaPreviousTrack',
+    () => windows.main.dispatch('previousTrack')
+  )
 }

 function disable () {
  // Return the media key to the OS, so other apps can use it.
  electron.globalShortcut.unregister('MediaPlayPause')
+  electron.globalShortcut.unregister('MediaNextTrack')
+  electron.globalShortcut.unregister('MediaPreviousTrack')
 }
--- a/src/main/squirrel-win32.js
+++ b/src/main/squirrel-win32.js
@@ -2,18 +2,18 @@ module.exports = {
  handleEvent
 }

-var cp = require('child_process')
-var electron = require('electron')
-var fs = require('fs')
-var os = require('os')
-var path = require('path')
+const cp = require('child_process')
+const electron = require('electron')
+const fs = require('fs')
+const os = require('os')
+const path = require('path')

-var app = electron.app
+const app = electron.app

-var handlers = require('./handlers')
+const handlers = require('./handlers')

-var EXE_NAME = path.basename(process.execPath)
-var UPDATE_EXE = path.join(process.execPath, '..', '..', 'Update.exe')
+const EXE_NAME = path.basename(process.execPath)
+const UPDATE_EXE = path.join(process.execPath, '..', '..', 'Update.exe')

 function handleEvent (cmd) {
  if (cmd === '--squirrel-install') {
@@ -73,9 +73,9 @@ function handleEvent (cmd) {
 * the output from standard out.
 */
 function spawn (command, args, cb) {
-  var stdout = ''
-
-  var child
+  let stdout = ''
+  let error = null
+  let child = null
  try {
    child = cp.spawn(command, args)
  } catch (err) {
@@ -90,10 +90,10 @@ function spawn (command, args, cb) {
    stdout += data
  })

-  var error = null
  child.on('error', function (processError) {
    error = processError
  })
+
  child.on('close', function (code, signal) {
    if (code !== 0 && !error) error = new Error('Command failed: #{signal || code}')
    if (error) error.stdout = stdout
@@ -122,12 +122,12 @@ function createShortcuts (cb) {
 * command.
 */
 function updateShortcuts (cb) {
-  var homeDir = os.homedir()
+  const homeDir = os.homedir()
  if (homeDir) {
-    var desktopShortcutPath = path.join(homeDir, 'Desktop', 'WebTorrent.lnk')
+    const desktopShortcutPath = path.join(homeDir, 'Desktop', 'WebTorrent.lnk')
    // If the desktop shortcut was deleted by the user, then keep it deleted.
    fs.access(desktopShortcutPath, function (err) {
-      var desktopShortcutExists = !err
+      const desktopShortcutExists = !err
      createShortcuts(function () {
        if (desktopShortcutExists) {
          cb()
--- a/src/main/startup.js
+++ b/src/main/startup.js
@@ -0,0 +1,36 @@
+module.exports = {
+  install,
+  uninstall
+}
+
+const config = require('../config')
+const AutoLaunch = require('auto-launch')
+const { app } = require('electron')
+
+// On Mac, work around a bug in auto-launch where it opens a Terminal window
+// See https://github.com/Teamwork/node-auto-launch/issues/28#issuecomment-222194437
+const appPath = process.platform === 'darwin'
+  ? app.getPath('exe').replace(/\.app\/Content.*/, '.app')
+  : undefined // Use the default
+
+const appLauncher = new AutoLaunch({
+  name: config.APP_NAME,
+  path: appPath,
+  isHidden: true
+})
+
+function install () {
+  return appLauncher
+    .isEnabled()
+    .then(enabled => {
+      if (!enabled) return appLauncher.enable()
+    })
+}
+
+function uninstall () {
+  return appLauncher
+    .isEnabled()
+    .then(enabled => {
+      if (enabled) return appLauncher.disable()
+    })
+}
--- a/src/main/thumbar.js
+++ b/src/main/thumbar.js
@@ -2,7 +2,8 @@ module.exports = {
  disable,
  enable,
  onPlayerPause,
-  onPlayerPlay
+  onPlayerPlay,
+  onPlayerUpdate
 }

 /**
@@ -11,44 +12,80 @@ module.exports = {
 * or activating the window.
 */

-var path = require('path')
-var config = require('../config')
+const path = require('path')
+const config = require('../config')

-var windows = require('./windows')
+const windows = require('./windows')
+
+const PREV_ICON = path.join(config.STATIC_PATH, 'PreviousTrackThumbnailBarButton.png')
+const PLAY_ICON = path.join(config.STATIC_PATH, 'PlayThumbnailBarButton.png')
+const PAUSE_ICON = path.join(config.STATIC_PATH, 'PauseThumbnailBarButton.png')
+const NEXT_ICON = path.join(config.STATIC_PATH, 'NextTrackThumbnailBarButton.png')
+
+// Array indices for each button
+const PREV = 0
+const PLAY_PAUSE = 1
+const NEXT = 2
+
+let buttons = []

 /**
 * Show the Windows thumbnail toolbar buttons.
 */
 function enable () {
-  update(false)
+  buttons = [
+    {
+      tooltip: 'Previous Track',
+      icon: PREV_ICON,
+      click: () => windows.main.dispatch('previousTrack')
+    },
+    {
+      tooltip: 'Pause',
+      icon: PAUSE_ICON,
+      click: () => windows.main.dispatch('playPause')
+    },
+    {
+      tooltip: 'Next Track',
+      icon: NEXT_ICON,
+      click: () => windows.main.dispatch('nextTrack')
+    }
+  ]
+  update()
 }

 /**
 * Hide the Windows thumbnail toolbar buttons.
 */
 function disable () {
-  windows.main.win.setThumbarButtons([])
+  buttons = []
+  update()
 }

 function onPlayerPause () {
-  update(true)
+  if (!isEnabled()) return
+  buttons[PLAY_PAUSE].tooltip = 'Play'
+  buttons[PLAY_PAUSE].icon = PLAY_ICON
+  update()
 }

 function onPlayerPlay () {
-  update(false)
+  if (!isEnabled()) return
+  buttons[PLAY_PAUSE].tooltip = 'Pause'
+  buttons[PLAY_PAUSE].icon = PAUSE_ICON
+  update()
 }

-function update (isPaused) {
-  var icon = isPaused
-    ? 'PlayThumbnailBarButton.png'
-    : 'PauseThumbnailBarButton.png'
+function onPlayerUpdate (state) {
+  if (!isEnabled()) return
+  buttons[PREV].flags = [ state.hasPrevious ? 'enabled' : 'disabled' ]
+  buttons[NEXT].flags = [ state.hasNext ? 'enabled' : 'disabled' ]
+  update()
+}

-  var buttons = [
-    {
-      tooltip: isPaused ? 'Play' : 'Pause',
-      icon: path.join(config.STATIC_PATH, icon),
-      click: () => windows.main.dispatch('playPause')
-    }
-  ]
+function isEnabled () {
+  return buttons.length > 0
+}
+
+function update () {
  windows.main.win.setThumbarButtons(buttons)
 }
--- a/src/main/tray.js
+++ b/src/main/tray.js
@@ -4,14 +4,14 @@ module.exports = {
  setWindowFocus
 }

-var electron = require('electron')
+const electron = require('electron')

-var app = electron.app
+const app = electron.app

-var config = require('../config')
-var windows = require('./windows')
+const config = require('../config')
+const windows = require('./windows')

-var tray
+let tray

 function init () {
  if (process.platform === 'linux') {
@@ -36,8 +36,8 @@ function setWindowFocus (flag) {
 }

 function initLinux () {
-  checkLinuxTraySupport(function (supportsTray) {
-    if (supportsTray) createTray()
+  checkLinuxTraySupport(function (err) {
+    if (!err) createTray()
  })
 }

@@ -49,16 +49,20 @@ function initWin32 () {
 * Check for libappindicator1 support before creating tray icon
 */
 function checkLinuxTraySupport (cb) {
-  var cp = require('child_process')
+  const cp = require('child_process')

  // Check that we're on Ubuntu (or another debian system) and that we have
  // libappindicator1. If WebTorrent was installed from the deb file, we should
  // always have it. If it was installed from the zip file, we might not.
  cp.exec('dpkg --get-selections libappindicator1', function (err, stdout) {
-    if (err) return cb(false)
+    if (err) return cb(err)
    // Unfortunately there's no cleaner way, as far as I can tell, to check
    // whether a debian package is installed:
-    cb(stdout.endsWith('\tinstall\n'))
+    if (stdout.endsWith('\tinstall\n')) {
+      cb(null)
+    } else {
+      cb(new Error('debian package not installed'))
+    }
  })
 }

@@ -74,7 +78,7 @@ function createTray () {
 }

 function updateTrayMenu () {
-  var contextMenu = electron.Menu.buildFromTemplate(getMenuTemplate())
+  const contextMenu = electron.Menu.buildFromTemplate(getMenuTemplate())
  tray.setContextMenu(contextMenu)
 }

--- a/src/main/updater.js
+++ b/src/main/updater.js
@@ -2,16 +2,17 @@ module.exports = {
  init
 }

-var electron = require('electron')
-var get = require('simple-get')
+const electron = require('electron')
+const get = require('simple-get')

-var config = require('../config')
-var log = require('./log')
-var windows = require('./windows')
+const config = require('../config')
+const log = require('./log')
+const windows = require('./windows')

-var AUTO_UPDATE_URL = config.AUTO_UPDATE_URL +
+const AUTO_UPDATE_URL = config.AUTO_UPDATE_URL +
  '?version=' + config.APP_VERSION +
-  '&platform=' + process.platform
+  '&platform=' + process.platform +
+  '&sysarch=' + config.OS_SYSARCH

 function init () {
  if (process.platform === 'linux') {
--- a/src/main/user-tasks.js
+++ b/src/main/user-tasks.js
@@ -2,9 +2,9 @@ module.exports = {
  init
 }

-var electron = require('electron')
+const electron = require('electron')

-var app = electron.app
+const app = electron.app

 /**
 * Add a user task menu to the app icon on right-click. (Windows)
--- a/src/main/windows/about.js
+++ b/src/main/windows/about.js
@@ -1,17 +1,17 @@
-var about = module.exports = {
+const about = module.exports = {
  init,
  win: null
 }

-var config = require('../../config')
-var electron = require('electron')
+const config = require('../../config')
+const electron = require('electron')

 function init () {
  if (about.win) {
    return about.win.show()
  }

-  var win = about.win = new electron.BrowserWindow({
+  const win = about.win = new electron.BrowserWindow({
    backgroundColor: '#ECECEC',
    center: true,
    fullscreen: false,
@@ -32,7 +32,7 @@ function init () {
  // No menu on the About window
  win.setMenu(null)

-  win.webContents.once('did-finish-load', function () {
+  win.once('ready-to-show', function () {
    win.show()
  })

--- a/src/main/windows/main.js
+++ b/src/main/windows/main.js
@@ -1,4 +1,4 @@
-var main = module.exports = {
+const main = module.exports = {
  dispatch,
  hide,
  init,
@@ -14,43 +14,59 @@ var main = module.exports = {
  win: null
 }

-var electron = require('electron')
+const electron = require('electron')
+const debounce = require('debounce')

-var app = electron.app
+const app = electron.app

-var config = require('../../config')
-var log = require('../log')
-var menu = require('../menu')
-var tray = require('../tray')
+const config = require('../../config')
+const log = require('../log')
+const menu = require('../menu')

-var HEADER_HEIGHT = 38
-var TORRENT_HEIGHT = 100
-
-function init () {
+function init (state, options) {
  if (main.win) {
    return main.win.show()
  }
-  var win = main.win = new electron.BrowserWindow({
+
+  const initialBounds = Object.assign(config.WINDOW_INITIAL_BOUNDS, state.saved.bounds)
+
+  const win = main.win = new electron.BrowserWindow({
    backgroundColor: '#282828',
+    backgroundThrottling: false, // do not throttle animations/timers when page is background
    darkTheme: true, // Forces dark theme (GTK+3)
+    height: initialBounds.height,
    icon: getIconPath(), // Window icon (Windows, Linux)
-    minWidth: config.WINDOW_MIN_WIDTH,
    minHeight: config.WINDOW_MIN_HEIGHT,
+    minWidth: config.WINDOW_MIN_WIDTH,
+    show: false,
    title: config.APP_WINDOW_TITLE,
    titleBarStyle: 'hidden-inset', // Hide title bar (Mac)
    useContentSize: true, // Specify web page size without OS chrome
-    width: 500,
-    height: HEADER_HEIGHT + (TORRENT_HEIGHT * 6) // header height + 5 torrents
+    width: initialBounds.width,
+    x: initialBounds.x,
+    y: initialBounds.y
  })

  win.loadURL(config.WINDOW_MAIN)

-  if (win.setSheetOffset) win.setSheetOffset(HEADER_HEIGHT)
+  win.once('ready-to-show', () => {
+    if (!options.hidden) win.show()
+  })
+
+  if (win.setSheetOffset) {
+    win.setSheetOffset(config.UI_HEADER_HEIGHT)
+  }

  win.webContents.on('dom-ready', function () {
    menu.onToggleFullScreen(main.win.isFullScreen())
  })

+  win.webContents.on('will-navigate', (e, url) => {
+    // Prevent drag-and-drop from navigating the Electron window, which can happen
+    // before our drag-and-drop handlers have been initialized.
+    e.preventDefault()
+  })
+
  win.on('blur', onWindowBlur)
  win.on('focus', onWindowFocus)

@@ -69,10 +85,23 @@ function init () {
    win.setMenuBarVisibility(true)
  })

+  win.on('move', debounce(function (e) {
+    send('windowBoundsChanged', e.sender.getBounds())
+  }, 1000))
+
+  win.on('resize', debounce(function (e) {
+    send('windowBoundsChanged', e.sender.getBounds())
+  }, 1000))
+
  win.on('close', function (e) {
-    if (process.platform !== 'darwin' && !tray.hasTray()) {
-      app.quit()
-    } else if (!app.isQuitting) {
+    if (process.platform !== 'darwin') {
+      const tray = require('../tray')
+      if (!tray.hasTray()) {
+        app.quit()
+        return
+      }
+    }
+    if (!app.isQuitting) {
      e.preventDefault()
      hide()
    }
@@ -85,7 +114,7 @@ function dispatch (...args) {

 function hide () {
  if (!main.win) return
-  main.win.send('dispatch', 'backToList')
+  dispatch('backToList')
  main.win.hide()
 }

@@ -114,7 +143,7 @@ function setBounds (bounds, maximize) {
  }

  // Maximize or minimize, if the second argument is present
-  var willBeMaximized
+  let willBeMaximized
  if (maximize === true) {
    if (!main.win.isMaximized()) {
      log('setBounds: maximizing')
@@ -136,9 +165,9 @@ function setBounds (bounds, maximize) {
    log('setBounds: setting bounds to ' + JSON.stringify(bounds))
    if (bounds.x === null && bounds.y === null) {
      // X and Y not specified? By default, center on current screen
-      var scr = electron.screen.getDisplayMatching(main.win.getBounds())
-      bounds.x = Math.round(scr.bounds.x + scr.bounds.width / 2 - bounds.width / 2)
-      bounds.y = Math.round(scr.bounds.y + scr.bounds.height / 2 - bounds.height / 2)
+      const scr = electron.screen.getDisplayMatching(main.win.getBounds())
+      bounds.x = Math.round(scr.bounds.x + (scr.bounds.width / 2) - (bounds.width / 2))
+      bounds.y = Math.round(scr.bounds.y + (scr.bounds.height / 2) - (bounds.height / 2))
      log('setBounds: centered to ' + JSON.stringify(bounds))
    }
    // Resize the window's content area (so window border doesn't need to be taken
@@ -211,12 +240,20 @@ function toggleFullScreen (flag) {

 function onWindowBlur () {
  menu.setWindowFocus(false)
-  tray.setWindowFocus(false)
+
+  if (process.platform !== 'darwin') {
+    const tray = require('../tray')
+    tray.setWindowFocus(false)
+  }
 }

 function onWindowFocus () {
  menu.setWindowFocus(true)
-  tray.setWindowFocus(true)
+
+  if (process.platform !== 'darwin') {
+    const tray = require('../tray')
+    tray.setWindowFocus(true)
+  }
 }

 function getIconPath () {
--- a/src/main/windows/webtorrent.js
+++ b/src/main/windows/webtorrent.js
@@ -1,4 +1,4 @@
-var webtorrent = module.exports = {
+const webtorrent = module.exports = {
  init,
  send,
  show,
@@ -6,14 +6,14 @@ var webtorrent = module.exports = {
  win: null
 }

-var electron = require('electron')
+const electron = require('electron')

-var config = require('../../config')
-var log = require('../log')
+const config = require('../../config')

 function init () {
-  var win = webtorrent.win = new electron.BrowserWindow({
+  const win = webtorrent.win = new electron.BrowserWindow({
    backgroundColor: '#1E1E1E',
+    backgroundThrottling: false, // do not throttle animations/timers when page is background
    center: true,
    fullscreen: false,
    fullscreenable: false,
@@ -52,7 +52,6 @@ function send (...args) {

 function toggleDevTools () {
  if (!webtorrent.win) return
-  log('toggleDevTools')
  if (webtorrent.win.webContents.isDevToolsOpened()) {
    webtorrent.win.webContents.closeDevTools()
    webtorrent.win.hide()
--- a/src/renderer/components/header.js
+++ b/src/renderer/components/header.js
@@ -4,9 +4,12 @@ const {dispatcher} = require('../lib/dispatcher')

 class Header extends React.Component {
  render () {
-    var loc = this.props.state.location
+    const loc = this.props.state.location
    return (
-      <div className='header'>
+      <div className='header'
+        onMouseMove={dispatcher('mediaMouseMoved')}
+        onMouseEnter={dispatcher('mediaControlsMouseEnter')}
+        onMouseLeave={dispatcher('mediaControlsMouseLeave')}>
        {this.getTitle()}
        <div className='nav left float-left'>
          <i
@@ -31,12 +34,12 @@ class Header extends React.Component {

  getTitle () {
    if (process.platform !== 'darwin') return null
-    var state = this.props.state
+    const state = this.props.state
    return (<div className='title ellipsis'>{state.window.title}</div>)
  }

  getAddButton () {
-    var state = this.props.state
+    const state = this.props.state
    if (state.location.url() !== 'home') return null
    return (
      <i
--- a/src/renderer/components/heading.js
+++ b/src/renderer/components/heading.js
@@ -17,15 +17,14 @@ class Heading extends React.Component {

  render () {
    const HeadingTag = 'h' + this.props.level
+    const style = {
+      color: colors.grey100,
+      fontSize: 20,
+      marginBottom: 15,
+      marginTop: 30
+    }
    return (
-      <HeadingTag
-        style={{
-          color: colors.grey100,
-          fontSize: 20,
-          marginBottom: 15,
-          marginTop: 30
-        }}
-      >
+      <HeadingTag style={style}>
        {this.props.children}
      </HeadingTag>
    )
--- a/src/renderer/components/modal-ok-cancel.js
+++ b/src/renderer/components/modal-ok-cancel.js
@@ -0,0 +1,25 @@
+const React = require('react')
+const FlatButton = require('material-ui/FlatButton').default
+const RaisedButton = require('material-ui/RaisedButton').default
+
+module.exports = class ModalOKCancel extends React.Component {
+  render () {
+    const cancelStyle = { marginRight: 10, color: 'black' }
+    const {cancelText, onCancel, okText, onOK} = this.props
+    return (
+      <div className='float-right'>
+        <FlatButton
+          className='control cancel'
+          style={cancelStyle}
+          label={cancelText}
+          onClick={onCancel} />
+        <RaisedButton
+          className='control ok'
+          primary
+          label={okText}
+          onClick={onOK}
+          autoFocus />
+      </div>
+    )
+  }
+}
--- a/src/renderer/components/open-torrent-address-modal.js
+++ b/src/renderer/components/open-torrent-address-modal.js
@@ -1,32 +1,41 @@
 const React = require('react')
+const TextField = require('material-ui/TextField').default

+const ModalOKCancel = require('./modal-ok-cancel')
 const {dispatch, dispatcher} = require('../lib/dispatcher')

 module.exports = class OpenTorrentAddressModal extends React.Component {
  render () {
-    // TODO: dcposch remove janky inline <script>
    return (
      <div className='open-torrent-address-modal'>
        <p><label>Enter torrent address or magnet link</label></p>
-        <p>
-          <input id='add-torrent-url' type='text' onKeyPress={handleKeyPress} />
-        </p>
-        <p className='float-right'>
-          <button className='button button-flat' onClick={dispatcher('exitModal')}>Cancel</button>
-          <button className='button button-raised' onClick={handleOK}>OK</button>
-        </p>
-        <script>document.querySelector('#add-torrent-url').focus()</script>
+        <div>
+          <TextField
+            id='torrent-address-field'
+            className='control'
+            ref={(c) => { this.torrentURL = c }}
+            fullWidth
+            onKeyDown={handleKeyDown.bind(this)} />
+        </div>
+        <ModalOKCancel
+          cancelText='CANCEL'
+          onCancel={dispatcher('exitModal')}
+          okText='OK'
+          onOK={handleOK.bind(this)} />
      </div>
    )
  }
+
+  componentDidMount () {
+    this.torrentURL.input.focus()
+  }
 }

-function handleKeyPress (e) {
-  if (e.which === 13) handleOK() /* hit Enter to submit */
+function handleKeyDown (e) {
+  if (e.which === 13) handleOK.call(this) /* hit Enter to submit */
 }

 function handleOK () {
  dispatch('exitModal')
-  // TODO: dcposch use React refs instead
-  dispatch('addTorrent', document.querySelector('#add-torrent-url').value)
+  dispatch('addTorrent', this.torrentURL.input.value)
 }
--- a/src/renderer/components/path-selector.js
+++ b/src/renderer/components/path-selector.js
@@ -7,6 +7,9 @@ const remote = electron.remote
 const RaisedButton = require('material-ui/RaisedButton').default
 const TextField = require('material-ui/TextField').default

+// Lets you pick a file or directory.
+// Uses the system Open File dialog.
+// You can't edit the text field directly.
 class PathSelector extends React.Component {
  static get propTypes () {
    return {
@@ -26,7 +29,7 @@ class PathSelector extends React.Component {
  }

  handleClick () {
-    var opts = Object.assign({
+    const opts = Object.assign({
      defaultPath: this.props.value,
      properties: [ 'openFile', 'openDirectory' ]
    }, this.props.dialog)
@@ -43,48 +46,38 @@ class PathSelector extends React.Component {

  render () {
    const id = this.props.title.replace(' ', '-').toLowerCase()
+    const wrapperStyle = {
+      alignItems: 'center',
+      display: 'flex',
+      width: '100%'
+    }
+    const labelStyle = {
+      flex: '0 auto',
+      marginRight: 10,
+      overflow: 'hidden',
+      textOverflow: 'ellipsis',
+      whiteSpace: 'nowrap'
+    }
+    const textareaStyle = {
+      color: colors.grey50
+    }
+    const textFieldStyle = {
+      flex: '1'
+    }
+    const text = this.props.displayValue || this.props.value
+    const buttonStyle = {
+      marginLeft: 10
+    }
+
    return (
-      <div
-        className={this.props.className}
-        style={{
-          alignItems: 'center',
-          display: 'flex',
-          width: '100%'
-        }}
-      >
-        <div
-          className='label'
-          style={{
-            flex: '0 auto',
-            marginRight: 10,
-            overflow: 'hidden',
-            textOverflow: 'ellipsis',
-            whiteSpace: 'nowrap'
-          }}
-        >
+      <div className={this.props.className} style={wrapperStyle}>
+        <div className='label' style={labelStyle}>
          {this.props.title}:
        </div>
-        <TextField
-          className='control'
-          disabled
-          id={id}
-          inputStyle={{
-            color: colors.grey50
-          }}
-          style={{
-            flex: '1',
-            fontSize: 14
-          }}
-          value={this.props.displayValue || this.props.value}
-        />
-        <RaisedButton
-          className='control'
-          label='Change'
-          onClick={this.handleClick}
-          style={{
-            marginLeft: 10
-          }}
-        />
+        <TextField className='control' disabled id={id} value={text}
+          inputStyle={textareaStyle} style={textFieldStyle} />
+        <RaisedButton className='control' label='Change' onClick={this.handleClick}
+          style={buttonStyle} />
      </div>
    )
  }
--- a/src/renderer/components/remove-torrent-modal.js
+++ b/src/renderer/components/remove-torrent-modal.js
@@ -1,22 +1,24 @@
 const React = require('react')

+const ModalOKCancel = require('./modal-ok-cancel')
 const {dispatch, dispatcher} = require('../lib/dispatcher')

 module.exports = class RemoveTorrentModal extends React.Component {
  render () {
-    var state = this.props.state
-    var message = state.modal.deleteData
+    const state = this.props.state
+    const message = state.modal.deleteData
      ? 'Are you sure you want to remove this torrent from the list and delete the data file?'
      : 'Are you sure you want to remove this torrent from the list?'
-    var buttonText = state.modal.deleteData ? 'Remove Data' : 'Remove'
+    const buttonText = state.modal.deleteData ? 'REMOVE DATA' : 'REMOVE'

    return (
      <div>
        <p><strong>{message}</strong></p>
-        <p className='float-right'>
-          <button className='button button-flat' onClick={dispatcher('exitModal')}>Cancel</button>
-          <button className='button button-raised' onClick={handleRemove}>{buttonText}</button>
-        </p>
+        <ModalOKCancel
+          cancelText='CANCEL'
+          onCancel={dispatcher('exitModal')}
+          okText={buttonText}
+          onOK={handleRemove} />
      </div>
    )

--- a/src/renderer/components/show-more.js
+++ b/src/renderer/components/show-more.js
@@ -1,6 +1,6 @@
 const React = require('react')

-const FlatButton = require('material-ui/FlatButton').default
+const RaisedButton = require('material-ui/RaisedButton').default

 class ShowMore extends React.Component {
  static get propTypes () {
@@ -39,14 +39,12 @@ class ShowMore extends React.Component {
      ? this.props.hideLabel
      : this.props.showLabel
    return (
-      <div
-        style={this.props.style}
-      >
+      <div className='show-more' style={this.props.style}>
        {this.state.expanded ? this.props.children : null}
-        <FlatButton
+        <RaisedButton
+          className='control'
          onClick={this.handleClick}
-          label={label}
-        />
+          label={label} />
      </div>
    )
  }
--- a/src/renderer/components/unsupported-media-modal.js
+++ b/src/renderer/components/unsupported-media-modal.js
@@ -1,35 +1,35 @@
 const React = require('react')
 const electron = require('electron')
-const path = require('path')

+const ModalOKCancel = require('./modal-ok-cancel')
 const {dispatcher} = require('../lib/dispatcher')

 module.exports = class UnsupportedMediaModal extends React.Component {
  render () {
-    var state = this.props.state
-    var err = state.modal.error
-    var message = (err && err.getMessage)
+    const state = this.props.state
+    const err = state.modal.error
+    const message = (err && err.getMessage)
      ? err.getMessage()
      : err
-    var playerPath = state.saved.prefs.externalPlayerPath
-    var playerName = playerPath
-      ? path.basename(playerPath).split('.')[0]
-      : 'VLC'
-    var actionButton = state.modal.externalPlayerInstalled
-      ? (<button className='button-raised' onClick={dispatcher('openExternalPlayer')}>Play in {playerName}</button>)
-      : (<button className='button-raised' onClick={() => this.onInstall}>Install VLC</button>)
-    var playerMessage = state.modal.externalPlayerNotFound
+    const onAction = state.modal.externalPlayerInstalled
+      ? dispatcher('openExternalPlayer')
+      : () => this.onInstall()
+    const actionText = state.modal.externalPlayerInstalled
+      ? 'PLAY IN ' + state.getExternalPlayerName().toUpperCase()
+      : 'INSTALL VLC'
+    const errorMessage = state.modal.externalPlayerNotFound
      ? 'Couldn\'t run external player. Please make sure it\'s installed.'
      : ''
    return (
      <div>
        <p><strong>Sorry, we can't play that file.</strong></p>
        <p>{message}</p>
-        <p className='float-right'>
-          <button className='button-flat' onClick={dispatcher('backToList')}>Cancel</button>
-          {actionButton}
-        </p>
-        <p className='error-text'>{playerMessage}</p>
+        <ModalOKCancel
+          cancelText='CANCEL'
+          onCancel={dispatcher('backToList')}
+          okText={actionText}
+          onOK={onAction} />
+        <p className='error-text'>{errorMessage}</p>
      </div>
    )
  }
@@ -38,7 +38,7 @@ module.exports = class UnsupportedMediaModal extends React.Component {
    electron.shell.openExternal('http://www.videolan.org/vlc/')

    // TODO: dcposch send a dispatch rather than modifying state directly
-    var state = this.props.state
+    const state = this.props.state
    state.modal.externalPlayerInstalled = true // Assume they'll install it successfully
  }
 }
--- a/src/renderer/components/update-available-modal.js
+++ b/src/renderer/components/update-available-modal.js
@@ -1,19 +1,24 @@
 const React = require('react')
 const electron = require('electron')

+const ModalOKCancel = require('./modal-ok-cancel')
 const {dispatch} = require('../lib/dispatcher')

 module.exports = class UpdateAvailableModal extends React.Component {
  render () {
-    var state = this.props.state
+    const state = this.props.state
    return (
      <div className='update-available-modal'>
        <p><strong>A new version of WebTorrent is available: v{state.modal.version}</strong></p>
-        <p>We have an auto-updater for Windows and Mac. We don't have one for Linux yet, so you'll have to download the new version manually.</p>
-        <p className='float-right'>
-          <button className='button button-flat' onClick={handleSkip}>Skip This Release</button>
-          <button className='button button-raised' onClick={handleShow}>Show Download Page</button>
+        <p>
+          We have an auto-updater for Windows and Mac.
+          We don't have one for Linux yet, so you'll have to download the new version manually.
        </p>
+        <ModalOKCancel
+          cancelText='SKIP THIS RELEASE'
+          onCancel={handleSkip}
+          okText='SHOW DOWNLOAD PAGE'
+          onOK={handleShow} />
      </div>
    )

--- a/src/renderer/controllers/media-controller.js
+++ b/src/renderer/controllers/media-controller.js
@@ -1,6 +1,6 @@
-const electron = require('electron')
-
-const ipcRenderer = electron.ipcRenderer
+const {ipcRenderer} = require('electron')
+const telemetry = require('../lib/telemetry')
+const Playlist = require('../lib/playlist')

 // Controls local play back: the <video>/<audio> tag and VLC
 // Does not control remote casting (Chromecast etc)
@@ -10,7 +10,7 @@ module.exports = class MediaController {
  }

  mediaSuccess () {
-    this.state.playing.result = 'success'
+    telemetry.logPlayAttempt('success')
  }

  mediaStalled () {
@@ -18,9 +18,9 @@ module.exports = class MediaController {
  }

  mediaError (error) {
-    var state = this.state
+    const state = this.state
    if (state.location.url() === 'player') {
-      state.playing.result = 'error'
+      telemetry.logPlayAttempt('error')
      state.playing.location = 'error'
      ipcRenderer.send('checkForExternalPlayer', state.saved.prefs.externalPlayerPath)
      ipcRenderer.once('checkForExternalPlayer', function (e, isInstalled) {
@@ -42,14 +42,37 @@ module.exports = class MediaController {
    this.state.playing.mouseStationarySince = new Date().getTime()
  }

+  controlsMouseEnter () {
+    this.state.playing.mouseInControls = true
+    this.state.playing.mouseStationarySince = new Date().getTime()
+  }
+
+  controlsMouseLeave () {
+    this.state.playing.mouseInControls = false
+    this.state.playing.mouseStationarySince = new Date().getTime()
+  }
+
  openExternalPlayer () {
-    var state = this.state
-    ipcRenderer.send('openExternalPlayer', state.saved.prefs.externalPlayerPath, state.server.localURL, state.window.title)
+    const state = this.state
    state.playing.location = 'external'
+
+    const onServerRunning = function () {
+      state.playing.isReady = true
+      telemetry.logPlayAttempt('external')
+
+      const mediaURL = Playlist.getCurrentLocalURL(state)
+      ipcRenderer.send('openExternalPlayer',
+        state.saved.prefs.externalPlayerPath,
+        mediaURL,
+        state.window.title)
+    }
+
+    if (state.server != null) onServerRunning()
+    else ipcRenderer.once('wt-server-running', onServerRunning)
  }

  externalPlayerNotFound () {
-    var modal = this.state.modal
+    const modal = this.state.modal
    if (modal && modal.id === 'unsupported-media-modal') {
      modal.externalPlayerNotFound = true
    }
--- a/src/renderer/controllers/playback-controller.js
+++ b/src/renderer/controllers/playback-controller.js
@@ -4,10 +4,11 @@ const path = require('path')
 const Cast = require('../lib/cast')
 const {dispatch} = require('../lib/dispatcher')
 const telemetry = require('../lib/telemetry')
-const errors = require('../lib/errors')
+const {UnplayableFileError, UnplayableTorrentError} = require('../lib/errors')
 const sound = require('../lib/sound')
 const TorrentPlayer = require('../lib/torrent-player')
 const TorrentSummary = require('../lib/torrent-summary')
+const Playlist = require('../lib/playlist')
 const State = require('../lib/state')

 const ipcRenderer = electron.ipcRenderer
@@ -24,41 +25,45 @@ module.exports = class PlaybackController {
  // Play a file in a torrent.
  // * Start torrenting, if necessary
  // * Stream, if not already fully downloaded
-  // * If no file index is provided, pick the default file to play
+  // * If no file index is provided, restore the most recently viewed file or autoplay the first
  playFile (infoHash, index /* optional */) {
    this.pauseActiveTorrents(infoHash)

-    this.state.location.go({
-      url: 'player',
-      setup: (cb) => {
-        this.play()
-        this.openPlayer(infoHash, index, cb)
-      },
-      destroy: () => this.closePlayer()
-    }, (err) => {
-      if (err) dispatch('error', err)
-    })
-  }
+    const state = this.state
+    if (state.location.url() === 'player') {
+      this.updatePlayer(infoHash, index, false, (err) => {
+        if (err) dispatch('error', err)
+        else this.play()
+      })
+    } else {
+      let initialized = false
+      state.location.go({
+        url: 'player',
+        setup: (cb) => {
+          const torrentSummary = TorrentSummary.getByKey(state, infoHash)

-  pauseActiveTorrents (infoHash) {
-    // playback priority: pause all active torrents if needed
-    if (this.state.saved.prefs.highestPlaybackPriority) {
-      // do not pause active torrents if playing a fully downloaded torrent
-      var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
-      if (torrentSummary.status === 'seeding') return
+          if (index === undefined || initialized) index = torrentSummary.mostRecentFileIndex
+          if (index === undefined) index = torrentSummary.files.findIndex(TorrentPlayer.isPlayable)
+          if (index === undefined) return cb(new UnplayableTorrentError())

-      var params = {
-        filter: {status: /downloading|seeding/},
-        excluded: [infoHash]
-      }
-      dispatch('pauseAllTorrents', params)
+          initialized = true
+
+          this.openPlayer(infoHash, index, (err) => {
+            if (!err) this.play()
+            cb(err)
+          })
+        },
+        destroy: () => this.closePlayer()
+      }, (err) => {
+        if (err) dispatch('error', err)
+      })
    }
  }

  // Open a file in OS default app.
  openItem (infoHash, index) {
-    var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
-    var filePath = path.join(
+    const torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
+    const filePath = path.join(
      torrentSummary.path,
      torrentSummary.files[index].path)
    ipcRenderer.send('openItem', filePath)
@@ -66,12 +71,12 @@ module.exports = class PlaybackController {

  // Toggle (play or pause) the currently playing media
  playPause () {
-    var state = this.state
+    const state = this.state
    if (state.location.url() !== 'player') return

    // force rerendering if window is hidden,
    // in order to bypass `raf` and play/pause media immediately
-    var mediaTag = document.querySelector('video,audio')
+    const mediaTag = document.querySelector('video,audio')
    if (!state.window.isVisible && mediaTag) {
      if (state.playing.isPaused) mediaTag.play()
      else mediaTag.pause()
@@ -81,9 +86,44 @@ module.exports = class PlaybackController {
    else this.pause()
  }

+  pauseActiveTorrents (infoHash) {
+    // Playback Priority: pause all active torrents if needed.
+    if (this.state.saved.prefs.highestPlaybackPriority) {
+      // Do not pause active torrents if playing a fully downloaded torrent.
+      var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
+      if (torrentSummary.status === 'seeding') return
+
+      dispatch('prioritizeTorrent', infoHash)
+    }
+  }
+
+  // Play next file in list (if any)
+  nextTrack () {
+    const state = this.state
+    if (Playlist.hasNext(state) && state.playing.location !== 'external') {
+      this.updatePlayer(
+          state.playing.infoHash, Playlist.getNextIndex(state), false, (err) => {
+            if (err) dispatch('error', err)
+            else this.play()
+          })
+    }
+  }
+
+  // Play previous track in list (if any)
+  previousTrack () {
+    const state = this.state
+    if (Playlist.hasPrevious(state) && state.playing.location !== 'external') {
+      this.updatePlayer(
+        state.playing.infoHash, Playlist.getPreviousIndex(state), false, (err) => {
+          if (err) dispatch('error', err)
+          else this.play()
+        })
+    }
+  }
+
  // Play (unpause) the current media
  play () {
-    var state = this.state
+    const state = this.state
    if (!state.playing.isPaused) return
    state.playing.isPaused = false
    if (isCasting(state)) {
@@ -94,7 +134,7 @@ module.exports = class PlaybackController {

  // Pause the currently playing media
  pause () {
-    var state = this.state
+    const state = this.state
    if (state.playing.isPaused) return
    state.playing.isPaused = true
    if (isCasting(state)) {
@@ -123,25 +163,23 @@ module.exports = class PlaybackController {
  // to 0.25 (quarter-speed playback), then goes to -0.25, -0.5, -1, -2, etc
  // until -16 (fast rewind)
  changePlaybackRate (direction) {
-    var state = this.state
-    var rate = state.playing.playbackRate
-    if (direction > 0 && rate >= 0.25 && rate < 2) {
+    const state = this.state
+    let rate = state.playing.playbackRate
+    if (direction > 0 && rate < 2) {
      rate += 0.25
    } else if (direction < 0 && rate > 0.25 && rate <= 2) {
      rate -= 0.25
-    } else if (direction < 0 && rate === 0.25) { /* when we set playback rate at 0 in html 5, playback hangs ;( */
-      rate = -1
-    } else if (direction > 0 && rate === -1) {
-      rate = 0.25
-    } else if ((direction > 0 && rate >= 1 && rate < 16) || (direction < 0 && rate > -16 && rate <= -1)) {
+    } else if (direction > 0 && rate >= 1 && rate < 16) {
      rate *= 2
-    } else if ((direction < 0 && rate > 1 && rate <= 16) || (direction > 0 && rate >= -16 && rate < -1)) {
+    } else if (direction < 0 && rate > 1 && rate <= 16) {
      rate /= 2
    }
    state.playing.playbackRate = rate
    if (isCasting(state) && !Cast.setRate(rate)) {
      state.playing.playbackRate = 1
    }
+    // Wait a bit before we hide the controls and header again
+    state.playing.mouseStationarySince = new Date().getTime()
  }

  // Change the volume, in range [0, 1], by some amount
@@ -156,7 +194,7 @@ module.exports = class PlaybackController {
    // check if its in [0.0 - 1.0] range
    volume = Math.max(0, Math.min(1, volume))

-    var state = this.state
+    const state = this.state
    if (isCasting(state)) {
      Cast.setVolume(volume)
    } else {
@@ -170,12 +208,8 @@ module.exports = class PlaybackController {
  // * The video is paused
  // * The video is playing remotely on Chromecast or Airplay
  showOrHidePlayerControls () {
-    var state = this.state
-    var hideControls = state.location.url() === 'player' &&
-      state.playing.mouseStationarySince !== 0 &&
-      new Date().getTime() - state.playing.mouseStationarySince > 2000 &&
-      !state.playing.isPaused &&
-      state.playing.location === 'local'
+    const state = this.state
+    const hideControls = state.shouldHidePlayerControls()

    if (hideControls !== state.playing.hideControls) {
      state.playing.hideControls = hideControls
@@ -186,60 +220,81 @@ module.exports = class PlaybackController {

  // Opens the video player to a specific torrent
  openPlayer (infoHash, index, cb) {
-    var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
+    const state = this.state
+    const torrentSummary = TorrentSummary.getByKey(state, infoHash)

-    // automatically choose which file in the torrent to play, if necessary
-    if (index === undefined) index = torrentSummary.defaultPlayFileIndex
-    if (index === undefined) index = TorrentPlayer.pickFileToPlay(torrentSummary.files)
-    if (index === undefined) return cb(new errors.UnplayableError())
+    state.playing.infoHash = torrentSummary.infoHash
+    state.playing.isReady = false

    // update UI to show pending playback
-    if (torrentSummary.progress !== 1) sound.play('PLAY')
-    // TODO: remove torrentSummary.playStatus
-    torrentSummary.playStatus = 'requested'
-    this.update()
+    sound.play('PLAY')

-    var timeout = setTimeout(() => {
-      telemetry.logPlayAttempt('timeout')
-      // TODO: remove torrentSummary.playStatus
-      torrentSummary.playStatus = 'timeout' /* no seeders available? */
-      sound.play('ERROR')
-      cb(new Error('Playback timed out. Try again.'))
-      this.update()
-    }, 10000) /* give it a few seconds */
+    this.startServer(torrentSummary)
+    ipcRenderer.send('onPlayerOpen')
+    this.updatePlayer(infoHash, index, true, cb)
+  }
+
+  // Starts WebTorrent server for media streaming
+  startServer (torrentSummary) {
+    const state = this.state

    if (torrentSummary.status === 'paused') {
      dispatch('startTorrentingSummary', torrentSummary.torrentKey)
      ipcRenderer.once('wt-ready-' + torrentSummary.infoHash,
-        () => this.openPlayerFromActiveTorrent(torrentSummary, index, timeout, cb))
+        () => onTorrentReady())
    } else {
-      this.openPlayerFromActiveTorrent(torrentSummary, index, timeout, cb)
+      onTorrentReady()
+    }
+
+    function onTorrentReady () {
+      ipcRenderer.send('wt-start-server', torrentSummary.infoHash)
+      ipcRenderer.once('wt-server-running', () => { state.playing.isReady = true })
    }
  }

-  openPlayerFromActiveTorrent (torrentSummary, index, timeout, cb) {
-    var fileSummary = torrentSummary.files[index]
+  // Called each time the current file changes
+  updatePlayer (infoHash, index, resume, cb) {
+    const state = this.state
+
+    const torrentSummary = TorrentSummary.getByKey(state, infoHash)
+    const fileSummary = torrentSummary.files[index]
+
+    if (!TorrentPlayer.isPlayable(fileSummary)) {
+      torrentSummary.mostRecentFileIndex = undefined
+      return cb(new UnplayableFileError())
+    }
+
+    torrentSummary.mostRecentFileIndex = index

    // update state
-    var state = this.state
-    state.playing.infoHash = torrentSummary.infoHash
+    state.playing.infoHash = infoHash
    state.playing.fileIndex = index
    state.playing.type = TorrentPlayer.isVideo(fileSummary) ? 'video'
      : TorrentPlayer.isAudio(fileSummary) ? 'audio'
      : 'other'

    // pick up where we left off
-    if (fileSummary.currentTime) {
-      var fraction = fileSummary.currentTime / fileSummary.duration
-      var secondsLeft = fileSummary.duration - fileSummary.currentTime
+    let jumpToTime = 0
+    if (resume && fileSummary.currentTime) {
+      const fraction = fileSummary.currentTime / fileSummary.duration
+      const secondsLeft = fileSummary.duration - fileSummary.currentTime
      if (fraction < 0.9 && secondsLeft > 10) {
-        state.playing.jumpToTime = fileSummary.currentTime
+        jumpToTime = fileSummary.currentTime
      }
    }
+    state.playing.jumpToTime = jumpToTime

    // if it's audio, parse out the metadata (artist, title, etc)
-    if (state.playing.type === 'audio' && !fileSummary.audioInfo) {
-      ipcRenderer.send('wt-get-audio-metadata', torrentSummary.infoHash, index)
+    if (torrentSummary.status === 'paused') {
+      ipcRenderer.once('wt-ready-' + torrentSummary.infoHash, getAudioMetadata)
+    } else {
+      getAudioMetadata()
+    }
+
+    function getAudioMetadata () {
+      if (state.playing.type === 'audio' && !fileSummary.audioInfo) {
+        ipcRenderer.send('wt-get-audio-metadata', torrentSummary.infoHash, index)
+      }
    }

    // if it's video, check for subtitles files that are done downloading
@@ -250,41 +305,28 @@ module.exports = class PlaybackController {
      dispatch('addSubtitles', [fileSummary.selectedSubtitle], true)
    }

-    ipcRenderer.send('wt-start-server', torrentSummary.infoHash, index)
-    ipcRenderer.once('wt-server-' + torrentSummary.infoHash, (e, info) => {
-      clearTimeout(timeout)
+    state.window.title = fileSummary.name

-      // if we timed out (user clicked play a long time ago), don't autoplay
-      var timedOut = torrentSummary.playStatus === 'timeout'
-      delete torrentSummary.playStatus
-      if (timedOut) {
-        ipcRenderer.send('wt-stop-server')
-        return this.update()
-      }
-
-      state.window.title = torrentSummary.files[state.playing.fileIndex].name
-
-      // play in VLC if set as default player (Preferences / Playback / Play in VLC)
-      if (this.state.saved.prefs.openExternalPlayer) {
-        dispatch('openExternalPlayer')
-        this.update()
-        cb()
-        return
-      }
-
-      // otherwise, play the video
+    // play in VLC if set as default player (Preferences / Playback / Play in VLC)
+    if (this.state.saved.prefs.openExternalPlayer) {
+      dispatch('openExternalPlayer')
      this.update()
-
-      ipcRenderer.send('onPlayerOpen')
      cb()
-    })
+      return
+    }
+
+    // otherwise, play the video
+    this.update()
+
+    ipcRenderer.send('onPlayerUpdate', Playlist.hasNext(state), Playlist.hasPrevious(state))
+    cb()
  }

  closePlayer () {
    console.log('closePlayer')

    // Quit any external players, like Chromecast/Airplay/etc or VLC
-    var state = this.state
+    const state = this.state
    if (isCasting(state)) {
      Cast.stop()
    }
@@ -295,12 +337,7 @@ module.exports = class PlaybackController {
    // Save volume (this session only, not in state.saved)
    state.previousVolume = state.playing.volume

-    // Telemetry: track what happens after the user clicks play
-    var result = state.playing.result // 'success' or 'error'
-    if (result === 'success') telemetry.logPlayAttempt('success') // first frame displayed
-    else if (result === 'error') telemetry.logPlayAttempt('error') // codec missing, etc
-    else if (result === undefined) telemetry.logPlayAttempt('abandoned') // user exited before first frame
-    else console.error('Unknown state.playing.result', state.playing.result)
+    if (!state.playing.isReady) telemetry.logPlayAttempt('abandoned') // user gave up waiting

    // Reset the window contents back to the home screen
    state.playing = State.getDefaultPlayState()
@@ -317,7 +354,7 @@ module.exports = class PlaybackController {

    ipcRenderer.send('onPlayerClose')

-    // playback priority: resume previously paused downloads
+    // Playback Priority: resume previously paused downloads.
    if (this.state.saved.prefs.highestPlaybackPriority) {
      dispatch('resumePausedTorrents')
    }
--- a/src/renderer/controllers/prefs-controller.js
+++ b/src/renderer/controllers/prefs-controller.js
@@ -1,4 +1,3 @@
-const State = require('../lib/state')
 const {dispatch} = require('../lib/dispatcher')
 const ipcRenderer = require('electron').ipcRenderer

@@ -11,13 +10,15 @@ module.exports = class PrefsController {

  // Goes to the Preferences screen
  show () {
-    var state = this.state
+    const state = this.state
    state.location.go({
      url: 'preferences',
      setup: function (cb) {
        // initialize preferences
        state.window.title = 'Preferences'
-        state.unsaved = Object.assign(state.unsaved || {}, {prefs: state.saved.prefs || {}})
+        state.unsaved = Object.assign(state.unsaved || {}, {
+          prefs: Object.assign({}, state.saved.prefs)
+        })
        ipcRenderer.send('setAllowNav', false)
        cb()
      },
@@ -32,25 +33,29 @@ module.exports = class PrefsController {
  // For example: updatePreferences('foo.bar', 'baz')
  // Call save() to save to config.json
  update (property, value) {
-    var path = property.split('.')
-    var key = this.state.unsaved.prefs
-    for (var i = 0; i < path.length - 1; i++) {
-      if (typeof key[path[i]] === 'undefined') {
-        key[path[i]] = {}
+    const path = property.split('.')
+    let obj = this.state.unsaved.prefs
+    let i
+    for (i = 0; i < path.length - 1; i++) {
+      if (typeof obj[path[i]] === 'undefined') {
+        obj[path[i]] = {}
      }
-      key = key[path[i]]
+      obj = obj[path[i]]
    }
-    key[path[i]] = value
+    obj[path[i]] = value
  }

  // All unsaved prefs take effect atomically, and are saved to config.json
  save () {
-    var state = this.state
+    const state = this.state
    if (state.unsaved.prefs.isFileHandler !== state.saved.prefs.isFileHandler) {
      ipcRenderer.send('setDefaultFileHandler', state.unsaved.prefs.isFileHandler)
    }
+    if (state.unsaved.prefs.startup !== state.saved.prefs.startup) {
+      ipcRenderer.send('setStartup', state.unsaved.prefs.startup)
+    }
    state.saved.prefs = Object.assign(state.saved.prefs || {}, state.unsaved.prefs)
-    State.save(state)
+    dispatch('stateSaveImmediate')
    dispatch('checkDownloadPath')
  }
 }
--- a/src/renderer/controllers/subtitles-controller.js
+++ b/src/renderer/controllers/subtitles-controller.js
@@ -1,5 +1,5 @@
 const electron = require('electron')
-const fs = require('fs-extra')
+const fs = require('fs')
 const path = require('path')
 const parallel = require('run-parallel')

@@ -28,36 +28,35 @@ module.exports = class SubtitlesController {
  }

  toggleSubtitlesMenu () {
-    var subtitles = this.state.playing.subtitles
+    const subtitles = this.state.playing.subtitles
    subtitles.showMenu = !subtitles.showMenu
  }

  addSubtitles (files, autoSelect) {
-    var state = this.state
    // Subtitles are only supported when playing video files
-    if (state.playing.type !== 'video') return
+    if (this.state.playing.type !== 'video') return
    if (files.length === 0) return
-    var subtitles = state.playing.subtitles
+    const subtitles = this.state.playing.subtitles

    // Read the files concurrently, then add all resulting subtitle tracks
-    var tasks = files.map((file) => (cb) => loadSubtitle(file, cb))
+    const tasks = files.map((file) => (cb) => loadSubtitle(file, cb))
    parallel(tasks, function (err, tracks) {
      if (err) return dispatch('error', err)

-      for (var i = 0; i < tracks.length; i++) {
+      for (let i = 0; i < tracks.length; i++) {
        // No dupes allowed
-        var track = tracks[i]
-        var trackIndex = state.playing.subtitles.tracks
-          .findIndex((t) => track.filePath === t.filePath)
+        const track = tracks[i]
+        let trackIndex = subtitles.tracks.findIndex((t) =>
+          track.filePath === t.filePath)

        // Add the track
        if (trackIndex === -1) {
-          trackIndex = state.playing.subtitles.tracks.push(track) - 1
+          trackIndex = subtitles.tracks.push(track) - 1
        }

        // If we're auto-selecting a track, try to find one in the user's language
        if (autoSelect && (i === 0 || isSystemLanguage(track.language))) {
-          state.playing.subtitles.selectedIndex = trackIndex
+          subtitles.selectedIndex = trackIndex
        }
      }

@@ -68,46 +67,46 @@ module.exports = class SubtitlesController {

  checkForSubtitles () {
    if (this.state.playing.type !== 'video') return
-    var torrentSummary = this.state.getPlayingTorrentSummary()
+    const torrentSummary = this.state.getPlayingTorrentSummary()
    if (!torrentSummary || !torrentSummary.progress) return

    torrentSummary.progress.files.forEach((fp, ix) => {
      if (fp.numPieces !== fp.numPiecesPresent) return // ignore incomplete files
-      var file = torrentSummary.files[ix]
+      const file = torrentSummary.files[ix]
      if (!this.isSubtitle(file.name)) return
-      var filePath = path.join(torrentSummary.path, file.path)
+      const filePath = path.join(torrentSummary.path, file.path)
      this.addSubtitles([filePath], false)
    })
  }

  isSubtitle (file) {
-    var name = typeof file === 'string' ? file : file.name
-    var ext = path.extname(name).toLowerCase()
+    const name = typeof file === 'string' ? file : file.name
+    const ext = path.extname(name).toLowerCase()
    return ext === '.srt' || ext === '.vtt'
  }
 }

 function loadSubtitle (file, cb) {
  // Lazy load to keep startup fast
-  var concat = require('simple-concat')
-  var LanguageDetect = require('languagedetect')
-  var srtToVtt = require('srt-to-vtt')
+  const concat = require('simple-concat')
+  const LanguageDetect = require('languagedetect')
+  const srtToVtt = require('srt-to-vtt')

  // Read the .SRT or .VTT file, parse it, add subtitle track
-  var filePath = file.path || file
+  const filePath = file.path || file

-  var vttStream = fs.createReadStream(filePath).pipe(srtToVtt())
+  const vttStream = fs.createReadStream(filePath).pipe(srtToVtt())

  concat(vttStream, function (err, buf) {
    if (err) return dispatch('error', 'Can\'t parse subtitles file.')

    // Detect what language the subtitles are in
-    var vttContents = buf.toString().replace(/(.*-->.*)/g, '')
-    var langDetected = (new LanguageDetect()).detect(vttContents, 2)
+    const vttContents = buf.toString().replace(/(.*-->.*)/g, '')
+    let langDetected = (new LanguageDetect()).detect(vttContents, 2)
    langDetected = langDetected.length ? langDetected[0][0] : 'subtitle'
    langDetected = langDetected.slice(0, 1).toUpperCase() + langDetected.slice(1)

-    var track = {
+    const track = {
      buffer: 'data:text/vtt;base64,' + buf.toString('base64'),
      language: langDetected,
      label: langDetected,
@@ -121,18 +120,18 @@ function loadSubtitle (file, cb) {
 // Checks whether a language name like 'English' or 'German' matches the system
 // language, aka the current locale
 function isSystemLanguage (language) {
-  var iso639 = require('iso-639-1')
-  var osLangISO = window.navigator.language.split('-')[0] // eg 'en'
-  var langIso = iso639.getCode(language) // eg 'de' if language is 'German'
+  const iso639 = require('iso-639-1')
+  const osLangISO = window.navigator.language.split('-')[0] // eg 'en'
+  const langIso = iso639.getCode(language) // eg 'de' if language is 'German'
  return langIso === osLangISO
 }

 // Make sure we don't have two subtitle tracks with the same label
 // Labels each track by language, eg 'German', 'English', 'English 2', ...
 function relabelSubtitles (subtitles) {
-  var counts = {}
+  const counts = {}
  subtitles.tracks.forEach(function (track) {
-    var lang = track.language
+    const lang = track.language
    counts[lang] = (counts[lang] || 0) + 1
    track.label = counts[lang] > 1 ? (lang + ' ' + counts[lang]) : lang
  })
--- a/src/renderer/controllers/torrent-controller.js
+++ b/src/renderer/controllers/torrent-controller.js
@@ -2,7 +2,6 @@ const path = require('path')
 const ipcRenderer = require('electron').ipcRenderer

 const TorrentSummary = require('../lib/torrent-summary')
-const TorrentPlayer = require('../lib/torrent-player')
 const sound = require('../lib/sound')
 const {dispatch} = require('../lib/dispatcher')

@@ -12,12 +11,12 @@ module.exports = class TorrentController {
  }

  torrentInfoHash (torrentKey, infoHash) {
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    let torrentSummary = this.getTorrentSummary(torrentKey)
    console.log('got infohash for %s torrent %s',
      torrentSummary ? 'existing' : 'new', torrentKey)

    if (!torrentSummary) {
-      var torrents = this.state.saved.torrents
+      const torrents = this.state.saved.torrents

      // Check if an existing (non-active) torrent has the same info hash
      if (torrents.find((t) => t.infoHash === infoHash)) {
@@ -49,7 +48,7 @@ module.exports = class TorrentController {
    }
    dispatch('error', message)

-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
    if (torrentSummary) {
      console.log('Pausing torrent %s due to error: %s', torrentSummary.infoHash, message)
      torrentSummary.status = 'paused'
@@ -59,21 +58,20 @@ module.exports = class TorrentController {

  torrentMetadata (torrentKey, torrentInfo) {
    // Summarize torrent
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
    torrentSummary.status = 'downloading'
    torrentSummary.name = torrentSummary.displayName || torrentInfo.name
    torrentSummary.path = torrentInfo.path
    torrentSummary.magnetURI = torrentInfo.magnetURI
    // TODO: make torrentInfo immutable, save separately as torrentSummary.info
    // For now, check whether torrentSummary.files has already been set:
-    var hasDetailedFileInfo = torrentSummary.files && torrentSummary.files[0].path
+    const hasDetailedFileInfo = torrentSummary.files && torrentSummary.files[0].path
    if (!hasDetailedFileInfo) {
      torrentSummary.files = torrentInfo.files
    }
    if (!torrentSummary.selections) {
      torrentSummary.selections = torrentSummary.files.map((x) => true)
    }
-    torrentSummary.defaultPlayFileIndex = TorrentPlayer.pickFileToPlay(torrentInfo.files)
    dispatch('update')

    // Save the .torrent file, if it hasn't been saved already
@@ -85,7 +83,7 @@ module.exports = class TorrentController {

  torrentDone (torrentKey, torrentInfo) {
    // Update the torrent summary
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
    torrentSummary.status = 'seeding'

    // Notify the user that a torrent finished, but only if we actually DL'd at least part of it.
@@ -102,22 +100,18 @@ module.exports = class TorrentController {
  }

  torrentProgress (progressInfo) {
-    // Overall progress across all active torrents, 0 to 1
-    var progress = progressInfo.progress
-    var hasActiveTorrents = progressInfo.hasActiveTorrents
-
+    // Overall progress across all active torrents, 0 to 1, or -1 to hide the progress bar
    // Hide progress bar when client has no torrents, or progress is 100%
-    // TODO: isn't this equivalent to: if (progress === 1) ?
-    if (!hasActiveTorrents || progress === 1) {
-      progress = -1
-    }
+    const progress = (!progressInfo.hasActiveTorrents || progressInfo.progress === 1)
+      ? -1
+      : progressInfo.progress

    // Show progress bar under the WebTorrent taskbar icon, on OSX
    this.state.dock.progress = progress

    // Update progress for each individual torrent
    progressInfo.torrents.forEach((p) => {
-      var torrentSummary = this.getTorrentSummary(p.torrentKey)
+      const torrentSummary = this.getTorrentSummary(p.torrentKey)
      if (!torrentSummary) {
        console.log('warning: got progress for missing torrent %s', p.torrentKey)
        return
@@ -132,27 +126,28 @@ module.exports = class TorrentController {
  }

  torrentFileModtimes (torrentKey, fileModtimes) {
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
+    if (!torrentSummary) throw new Error('Not saving modtimes for deleted torrent ' + torrentKey)
    torrentSummary.fileModtimes = fileModtimes
-    dispatch('saveStateThrottled')
+    dispatch('stateSave')
  }

  torrentFileSaved (torrentKey, torrentFileName) {
    console.log('torrent file saved %s: %s', torrentKey, torrentFileName)
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
    torrentSummary.torrentFileName = torrentFileName
-    dispatch('saveStateThrottled')
+    dispatch('stateSave')
  }

  torrentPosterSaved (torrentKey, posterFileName) {
-    var torrentSummary = this.getTorrentSummary(torrentKey)
+    const torrentSummary = this.getTorrentSummary(torrentKey)
    torrentSummary.posterFileName = posterFileName
-    dispatch('saveStateThrottled')
+    dispatch('stateSave')
  }

  torrentAudioMetadata (infoHash, index, info) {
-    var torrentSummary = this.getTorrentSummary(infoHash)
-    var fileSummary = torrentSummary.files[index]
+    const torrentSummary = this.getTorrentSummary(infoHash)
+    const fileSummary = torrentSummary.files[index]
    fileSummary.audioInfo = info
    dispatch('update')
  }
@@ -169,7 +164,7 @@ module.exports = class TorrentController {
 }

 function getTorrentPath (torrentSummary) {
-  var itemPath = TorrentSummary.getFileOrFolder(torrentSummary)
+  let itemPath = TorrentSummary.getFileOrFolder(torrentSummary)
  if (torrentSummary.files.length > 1) {
    itemPath = path.dirname(itemPath)
  }
@@ -177,12 +172,12 @@ function getTorrentPath (torrentSummary) {
 }

 function showDoneNotification (torrent) {
-  var notif = new window.Notification('Download Complete', {
+  const notif = new window.Notification('Download Complete', {
    body: torrent.name,
    silent: true
  })

-  notif.onClick = function () {
+  notif.onclick = function () {
    ipcRenderer.send('show')
  }

--- a/src/renderer/controllers/torrent-list-controller.js
+++ b/src/renderer/controllers/torrent-list-controller.js
@@ -3,7 +3,7 @@ const path = require('path')
 const electron = require('electron')

 const {dispatch} = require('../lib/dispatcher')
-const State = require('../lib/state')
+const {TorrentKeyNotFoundError} = require('../lib/errors')
 const sound = require('../lib/sound')
 const TorrentSummary = require('../lib/torrent-summary')

@@ -17,21 +17,26 @@ module.exports = class TorrentListController {
    this.state = state
  }

-  // Adds a torrent to the list, starts downloading/seeding. TorrentID can be a
-  // magnet URI, infohash, or torrent file: https://github.com/feross/webtorrent#clientaddtorrentid-opts-function-ontorrent-torrent-
+  // Adds a torrent to the list, starts downloading/seeding.
+  // TorrentID can be a magnet URI, infohash, or torrent file: https://git.io/vik9M
  addTorrent (torrentId) {
    if (torrentId.path) {
      // Use path string instead of W3C File object
      torrentId = torrentId.path
    }

+    // Trim extra spaces off pasted magnet links
+    if (typeof torrentId === 'string') {
+      torrentId = torrentId.trim()
+    }
+
    // Allow a instant.io link to be pasted
    if (typeof torrentId === 'string' && instantIoRegex.test(torrentId)) {
      torrentId = torrentId.slice(torrentId.indexOf('#') + 1)
    }

-    var torrentKey = this.state.nextTorrentKey++
-    var path = this.state.saved.prefs.downloadPath
+    const torrentKey = this.state.nextTorrentKey++
+    const path = this.state.saved.prefs.downloadPath

    ipcRenderer.send('wt-start-torrenting', torrentKey, torrentId, path)

@@ -66,16 +71,16 @@ module.exports = class TorrentListController {

  // Creates a new torrent and start seeeding
  createTorrent (options) {
-    var state = this.state
-    var torrentKey = state.nextTorrentKey++
+    const state = this.state
+    const torrentKey = state.nextTorrentKey++
    ipcRenderer.send('wt-create-torrent', torrentKey, options)
    state.location.cancel()
  }

  // Starts downloading and/or seeding a given torrentSummary.
  startTorrentingSummary (torrentKey) {
-    var s = TorrentSummary.getByKey(this.state, torrentKey)
-    if (!s) throw new Error('Missing key: ' + torrentKey)
+    const s = TorrentSummary.getByKey(this.state, torrentKey)
+    if (!s) throw new TorrentKeyNotFoundError(torrentKey)

    // New torrent: give it a path
    if (!s.path) {
@@ -84,10 +89,16 @@ module.exports = class TorrentListController {
      return start()
    }

+    const fileOrFolder = TorrentSummary.getFileOrFolder(s)
+
+    // New torrent: metadata not yet received
+    if (!fileOrFolder) return start()
+
    // Existing torrent: check that the path is still there
-    fs.stat(TorrentSummary.getFileOrFolder(s), function (err) {
+    fs.stat(fileOrFolder, function (err) {
      if (err) {
        s.error = 'path-missing'
+        dispatch('backToList')
        return
      }
      start()
@@ -96,88 +107,89 @@ module.exports = class TorrentListController {
    function start () {
      ipcRenderer.send('wt-start-torrenting',
        s.torrentKey,
-        TorrentSummary.getTorrentID(s),
+        TorrentSummary.getTorrentId(s),
        s.path,
        s.fileModtimes,
        s.selections)
    }
  }

-  pauseAll ({filter, excluded}) {
-    this.state.saved.torrents.map((torrent) => {
-      // "excluded" is an array of torrents that should not be paused
-      if (excluded) {
-        var isExcluded = excluded.some((excludeInfoHash) => {
-          if (excludeInfoHash === torrent.infoHash) return true
-        })
-        if (isExcluded) return
-      }
-
-      // don't play sounds when pausing all
-      var wasPaused = this.pauseTorrent(torrent, false, filter)
-
-      // if torrent was paused add it to paused torrents collection
-      // we will use this collection to resume downloading when playback stops
-      if (wasPaused) this.state.saved.pausedTorrents.push(torrent.infoHash)
-    })
-  }
-
-  resumePausedTorrents () {
-    this.state.saved.pausedTorrents.map((infoHash) => {
-      var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
-      this.startTorrent(torrentSummary)
-    })
-
-    // reset paused torrents
-    this.state.saved.pausedTorrents = []
-  }
-
  // TODO: use torrentKey, not infoHash
  toggleTorrent (infoHash) {
-    var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
-
-    // start
+    const torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
    if (torrentSummary.status === 'paused') {
-      this.startTorrent(torrentSummary, true)
+      torrentSummary.status = 'new'
+      this.startTorrentingSummary(torrentSummary.torrentKey)
+      sound.play('ENABLE')
      return
-    }
+    } 

-    // pause
    this.pauseTorrent(torrentSummary, true)
  }

-  startTorrent (torrentSummary, playSound) {
-    torrentSummary.status = 'new'
-    this.startTorrentingSummary(torrentSummary.torrentKey)
-
-    if (playSound) sound.play('ENABLE')
+  pauseAllTorrents () {
+    this.state.saved.torrents.forEach((torrentSummary) => {
+      if (torrentSummary.status === 'downloading' ||
+          torrentSummary.status === 'seeding') {
+        torrentSummary.status = 'paused'
+        ipcRenderer.send('wt-stop-torrenting', torrentSummary.infoHash)
+      }
+    })
+    sound.play('DISABLE')
  }

-  pauseTorrent (torrentSummary, playSound, filter) {
-    if (filter && !this.matchesFilter(torrentSummary, filter)) return false
+  resumeAllTorrents () {
+    this.state.saved.torrents.forEach((torrentSummary) => {
+      if (torrentSummary.status === 'paused') {
+        torrentSummary.status = 'downloading'
+        this.startTorrentingSummary(torrentSummary.torrentKey)
+      }
+    })
+    sound.play('ENABLE')
+  }

+  pauseTorrent (torrentSummary, playSound) {
    torrentSummary.status = 'paused'
    ipcRenderer.send('wt-stop-torrenting', torrentSummary.infoHash)

    if (playSound) sound.play('DISABLE')
-    return true
  }

-  matchesFilter (torrentSummary, filter) {
-    var keys = Object.keys(filter)
-    var matches = keys.some((key) => {
-      if (!torrentSummary[key].match(filter[key])) return false
-      return true
+  prioritizeTorrent (infoHash) {
+    this.state.saved.torrents
+    .filter((torrent) => { // We're interested in active torrents only.
+      return (['downloading', 'seeding'].indexOf(torrent.status) !== -1)
    })
-    return matches
+    .map((torrent) => { // Pause all active torrents except the one that started playing.
+      if (infoHash === torrent.infoHash) return
+
+      // Pause torrent without playing sounds.
+      this.pauseTorrent(torrent, false)
+
+      this.state.saved.torrentsToResume.push(torrent.infoHash)
+    })
+
+    console.log('Playback Priority: paused torrents: ', this.state.saved.torrentsToResume)
+  }
+
+  resumePausedTorrents () {
+    console.log('Playback Priority: resuming paused torrents')
+    this.state.saved.torrentsToResume.map((infoHash) => {
+      this.toggleTorrent(infoHash)
+    })
+
+    // reset paused torrents
+    this.state.saved.torrentsToResume = []
  }

  toggleTorrentFile (infoHash, index) {
-    var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
+    const torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
    torrentSummary.selections[index] = !torrentSummary.selections[index]

    // Let the WebTorrent process know to start or stop fetching that file
-    ipcRenderer.send('wt-select-files', infoHash, torrentSummary.selections)
+    if (torrentSummary.status !== 'paused') {
+      ipcRenderer.send('wt-select-files', infoHash, torrentSummary.selections)
+    }
  }

  confirmDeleteTorrent (infoHash, deleteData) {
@@ -192,24 +204,25 @@ module.exports = class TorrentListController {
  deleteTorrent (infoHash, deleteData) {
    ipcRenderer.send('wt-stop-torrenting', infoHash)

-    var index = this.state.saved.torrents.findIndex((x) => x.infoHash === infoHash)
+    const index = this.state.saved.torrents.findIndex((x) => x.infoHash === infoHash)

    if (index > -1) {
-      var summary = this.state.saved.torrents[index]
+      const summary = this.state.saved.torrents[index]

      // remove torrent and poster file
      deleteFile(TorrentSummary.getTorrentPath(summary))
-      deleteFile(TorrentSummary.getPosterPath(summary)) // TODO: will the css path hack affect windows?
+      deleteFile(TorrentSummary.getPosterPath(summary))

      // optionally delete the torrent data
      if (deleteData) moveItemToTrash(summary)

      // remove torrent from saved list
      this.state.saved.torrents.splice(index, 1)
-      State.saveThrottled(this.state)
+      dispatch('stateSave')
    }

-    this.state.location.clearForward('player') // prevent user from going forward to a deleted torrent
+    // prevent user from going forward to a deleted torrent
+    this.state.location.clearForward('player')
    sound.play('DELETE')
  }

@@ -222,8 +235,8 @@ module.exports = class TorrentListController {
  }

  openTorrentContextMenu (infoHash) {
-    var torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
-    var menu = new electron.remote.Menu()
+    const torrentSummary = TorrentSummary.getByKey(this.state, infoHash)
+    const menu = new electron.remote.Menu()

    menu.append(new electron.remote.MenuItem({
      label: 'Remove From List',
@@ -261,39 +274,70 @@ module.exports = class TorrentListController {

    menu.append(new electron.remote.MenuItem({
      label: 'Save Torrent File As...',
-      click: () => saveTorrentFileAs(torrentSummary)
+      click: () => dispatch('saveTorrentFileAs', torrentSummary.torrentKey),
+      enabled: torrentSummary.torrentFileName != null
    }))

    menu.popup(electron.remote.getCurrentWindow())
  }
+
+  // Takes a torrentSummary or torrentKey
+  // Shows a Save File dialog, then saves the .torrent file wherever the user requests
+  saveTorrentFileAs (torrentKey) {
+    const torrentSummary = TorrentSummary.getByKey(this.state, torrentKey)
+    if (!torrentSummary) throw new Error('Missing torrentKey: ' + torrentKey)
+    const downloadPath = this.state.saved.prefs.downloadPath
+    const newFileName = path.parse(torrentSummary.name).name + '.torrent'
+    const win = electron.remote.getCurrentWindow()
+    const opts = {
+      title: 'Save Torrent File',
+      defaultPath: path.join(downloadPath, newFileName),
+      filters: [
+        { name: 'Torrent Files', extensions: ['torrent'] },
+        { name: 'All Files', extensions: ['*'] }
+      ]
+    }
+
+    electron.remote.dialog.showSaveDialog(win, opts, function (savePath) {
+      console.log('Saving torrent ' + torrentKey + ' to ' + savePath)
+      if (!savePath) return // They clicked Cancel
+      const torrentPath = TorrentSummary.getTorrentPath(torrentSummary)
+      fs.readFile(torrentPath, function (err, torrentFile) {
+        if (err) return dispatch('error', err)
+        fs.writeFile(savePath, torrentFile, function (err) {
+          if (err) return dispatch('error', err)
+        })
+      })
+    })
+  }
 }

 // Recursively finds {name, path, size} for all files in a folder
 // Calls `cb` on success, calls `onError` on failure
-function findFilesRecursive (paths, cb) {
+function findFilesRecursive (paths, cb_) {
  if (paths.length > 1) {
-    var numComplete = 0
-    var ret = []
+    let numComplete = 0
+    let ret = []
    paths.forEach(function (path) {
      findFilesRecursive([path], function (fileObjs) {
-        ret = ret.concat(fileObjs)
+        ret.push(...fileObjs)
        if (++numComplete === paths.length) {
          ret.sort((a, b) => a.path < b.path ? -1 : a.path > b.path)
-          cb(ret)
+          cb_(ret)
        }
      })
    })
    return
  }

-  var fileOrFolder = paths[0]
+  const fileOrFolder = paths[0]
  fs.stat(fileOrFolder, function (err, stat) {
    if (err) return dispatch('error', err)

    // Files: return name, path, and size
    if (!stat.isDirectory()) {
-      var filePath = fileOrFolder
-      return cb([{
+      const filePath = fileOrFolder
+      return cb_([{
        name: path.basename(filePath),
        path: filePath,
        size: stat.size
@@ -301,11 +345,11 @@ function findFilesRecursive (paths, cb) {
    }

    // Folders: recurse, make a list of all the files
-    var folderPath = fileOrFolder
+    const folderPath = fileOrFolder
    fs.readdir(folderPath, function (err, fileNames) {
      if (err) return dispatch('error', err)
-      var paths = fileNames.map((fileName) => path.join(folderPath, fileName))
-      findFilesRecursive(paths, cb)
+      const paths = fileNames.map((fileName) => path.join(folderPath, fileName))
+      findFilesRecursive(paths, cb_)
    })
  })
 }
@@ -319,33 +363,10 @@ function deleteFile (path) {

 // Delete all files in a torrent
 function moveItemToTrash (torrentSummary) {
-  var filePath = TorrentSummary.getFileOrFolder(torrentSummary)
+  const filePath = TorrentSummary.getFileOrFolder(torrentSummary)
  if (filePath) ipcRenderer.send('moveItemToTrash', filePath)
 }

 function showItemInFolder (torrentSummary) {
  ipcRenderer.send('showItemInFolder', TorrentSummary.getFileOrFolder(torrentSummary))
 }
-
-function saveTorrentFileAs (torrentSummary) {
-  var downloadPath = this.state.saved.prefs.downloadPath
-  var newFileName = path.parse(torrentSummary.name).name + '.torrent'
-  var opts = {
-    title: 'Save Torrent File',
-    defaultPath: path.join(downloadPath, newFileName),
-    filters: [
-      { name: 'Torrent Files', extensions: ['torrent'] },
-      { name: 'All Files', extensions: ['*'] }
-    ]
-  }
-  electron.remote.dialog.showSaveDialog(electron.remote.getCurrentWindow(), opts, function (savePath) {
-    if (!savePath) return // They clicked Cancel
-    var torrentPath = TorrentSummary.getTorrentPath(torrentSummary)
-    fs.readFile(torrentPath, function (err, torrentFile) {
-      if (err) return dispatch('error', err)
-      fs.writeFile(savePath, torrentFile, function (err) {
-        if (err) return dispatch('error', err)
-      })
-    })
-  })
-}
--- a/src/renderer/controllers/update-controller.js
+++ b/src/renderer/controllers/update-controller.js
@@ -1,4 +1,4 @@
-const State = require('../lib/state')
+const {dispatch} = require('../lib/dispatcher')

 // Controls the UI checking for new versions of the app, prompting install
 module.exports = class UpdateController {
@@ -8,7 +8,7 @@ module.exports = class UpdateController {

  // Shows a modal saying that we have an update
  updateAvailable (version) {
-    var skipped = this.state.saved.skippedVersions
+    const skipped = this.state.saved.skippedVersions
    if (skipped && skipped.includes(version)) {
      console.log('new version skipped by user: v' + version)
      return
@@ -18,9 +18,9 @@ module.exports = class UpdateController {

  // Don't show the modal again until the next version
  skipVersion (version) {
-    var skipped = this.state.saved.skippedVersions
+    let skipped = this.state.saved.skippedVersions
    if (!skipped) skipped = this.state.saved.skippedVersions = []
    skipped.push(version)
-    State.saveThrottled(this.state)
+    dispatch('stateSave')
  }
 }
--- a/src/renderer/lib/capture-video-frame.js
+++ b/src/renderer/lib/capture-video-frame.js
@@ -1,30 +0,0 @@
-module.exports = captureVideoFrame
-
-function captureVideoFrame (video, format) {
-  if (typeof video === 'string') {
-    video = document.querySelector(video)
-  }
-
-  if (video == null || video.nodeName !== 'VIDEO') {
-    throw new Error('First argument must be a <video> element or selector')
-  }
-
-  if (format == null) {
-    format = 'png'
-  }
-
-  if (format !== 'png' && format !== 'jpg' && format !== 'webp') {
-    throw new Error('Second argument must be one of "png", "jpg", or "webp"')
-  }
-
-  var canvas = document.createElement('canvas')
-  canvas.width = video.videoWidth
-  canvas.height = video.videoHeight
-
-  canvas.getContext('2d').drawImage(video, 0, 0)
-
-  var dataUri = canvas.toDataURL('image/' + format)
-  var data = dataUri.split(',')[1]
-
-  return new Buffer(data, 'base64')
-}
--- a/src/renderer/lib/cast.js
+++ b/src/renderer/lib/cast.js
@@ -13,25 +13,35 @@ module.exports = {
  setRate
 }

-// Lazy load these for a ~300ms improvement in startup time
-var airplayer, chromecasts, dlnacasts
+const config = require('../../config')
+const {CastingError} = require('./errors')

-var config = require('../../config')
+// Lazy load these for a ~300ms improvement in startup time
+let airplayer, chromecasts, dlnacasts

 // App state. Cast modifies state.playing and state.errors in response to events
-var state
+let state

 // Callback to notify module users when state has changed
-var update
+let update

 // setInterval() for updating cast status
-var statusInterval = null
+let statusInterval = null

 // Start looking for cast devices on the local network
 function init (appState, callback) {
  state = appState
  update = callback

+  // Don't actually cast during integration tests
+  // (Otherwise you'd need a physical Chromecast + AppleTV + DLNA TV to run them.)
+  if (config.IS_TEST) {
+    state.devices.chromecast = testPlayer('chromecast')
+    state.devices.airplay = testPlayer('airplay')
+    state.devices.dlna = testPlayer('dlna')
+    return
+  }
+
  // Load modules, scan the network for devices
  airplayer = require('airplayer')()
  chromecasts = require('chromecasts')()
@@ -57,9 +67,35 @@ function init (appState, callback) {
  })
 }

+// integration test player implementation
+function testPlayer (type) {
+  return {
+    getDevices,
+    open,
+    play,
+    pause,
+    stop,
+    status,
+    seek,
+    volume
+  }
+
+  function getDevices () {
+    return [{name: type + '-1'}, {name: type + '-2'}]
+  }
+
+  function open () {}
+  function play () {}
+  function pause () {}
+  function stop () {}
+  function status () {}
+  function seek () {}
+  function volume () {}
+}
+
 // chromecast player implementation
 function chromecastPlayer () {
-  var ret = {
+  const ret = {
    device: null,
    addDevice,
    getDevices,
@@ -95,8 +131,8 @@ function chromecastPlayer () {
  }

  function open () {
-    var torrentSummary = state.saved.torrents.find((x) => x.infoHash === state.playing.infoHash)
-    ret.device.play(state.server.networkURL, {
+    const torrentSummary = state.saved.torrents.find((x) => x.infoHash === state.playing.infoHash)
+    ret.device.play(state.server.networkURL + '/' + state.playing.fileIndex, {
      type: 'video/mp4',
      title: config.APP_NAME + ' - ' + torrentSummary.name
    }, function (err) {
@@ -126,13 +162,7 @@ function chromecastPlayer () {
  }

  function status () {
-    ret.device.status(function (err, status) {
-      if (err) return console.log('error getting %s status: %o', state.playing.location, err)
-      state.playing.isPaused = status.playerState === 'PAUSED'
-      state.playing.currentTime = status.currentTime
-      state.playing.volume = status.volume.muted ? 0 : status.volume.level
-      update()
-    })
+    ret.device.status(handleStatus)
  }

  function seek (time, callback) {
@@ -146,7 +176,7 @@ function chromecastPlayer () {

 // airplay player implementation
 function airplayPlayer () {
-  var ret = {
+  const ret = {
    device: null,
    addDevice,
    getDevices,
@@ -183,7 +213,7 @@ function airplayPlayer () {
  }

  function open () {
-    ret.device.play(state.server.networkURL, function (err, res) {
+    ret.device.play(state.server.networkURL + '/' + state.playing.fileIndex, function (err, res) {
      if (err) {
        state.playing.location = 'local'
        state.errors.push({
@@ -238,7 +268,7 @@ function airplayPlayer () {

 // DLNA player implementation
 function dlnaPlayer (player) {
-  var ret = {
+  const ret = {
    device: null,
    addDevice,
    getDevices,
@@ -274,8 +304,8 @@ function dlnaPlayer (player) {
  }

  function open () {
-    var torrentSummary = state.saved.torrents.find((x) => x.infoHash === state.playing.infoHash)
-    ret.device.play(state.server.networkURL, {
+    const torrentSummary = state.saved.torrents.find((x) => x.infoHash === state.playing.infoHash)
+    ret.device.play(state.server.networkURL + '/' + state.playing.fileIndex, {
      type: 'video/mp4',
      title: config.APP_NAME + ' - ' + torrentSummary.name,
      seek: state.playing.currentTime > 10 ? state.playing.currentTime : 0
@@ -306,13 +336,7 @@ function dlnaPlayer (player) {
  }

  function status () {
-    ret.device.status(function (err, status) {
-      if (err) return console.log('error getting %s status: %o', state.playing.location, err)
-      state.playing.isPaused = status.playerState === 'PAUSED'
-      state.playing.currentTime = status.currentTime
-      state.playing.volume = status.volume.level
-      update()
-    })
+    ret.device.status(handleStatus)
  }

  function seek (time, callback) {
@@ -328,10 +352,22 @@ function dlnaPlayer (player) {
  }
 }

+function handleStatus (err, status) {
+  if (err || !status) {
+    return console.log('error getting %s status: %o',
+      state.playing.location,
+      err || 'missing response')
+  }
+  state.playing.isPaused = status.playerState === 'PAUSED'
+  state.playing.currentTime = status.currentTime
+  state.playing.volume = status.volume.muted ? 0 : status.volume.level
+  update()
+}
+
 // Start polling cast device state, whenever we're connected
 function startStatusInterval () {
  statusInterval = setInterval(function () {
-    var player = getPlayer()
+    const player = getPlayer()
    if (player) player.status()
  }, 1000)
 }
@@ -350,23 +386,27 @@ function toggleMenu (location) {

  // Never cast to two devices at the same time
  if (state.playing.location !== 'local') {
-    throw new Error('You can\'t connect to ' + location + ' when already connected to another device')
+    throw new CastingError(
+      `You can't connect to ${location} when already connected to another device`
+    )
  }

  // Find all cast devices of the given type
-  var player = getPlayer(location)
-  var devices = player ? player.getDevices() : []
-  if (devices.length === 0) throw new Error('No ' + location + ' devices available')
+  const player = getPlayer(location)
+  const devices = player ? player.getDevices() : []
+  if (devices.length === 0) {
+    throw new CastingError(`No ${location} devices available`)
+  }

  // Show a menu
  state.devices.castMenu = {location, devices}
 }

 function selectDevice (index) {
-  var {location, devices} = state.devices.castMenu
+  const {location, devices} = state.devices.castMenu

  // Start casting
-  var player = getPlayer(location)
+  const player = getPlayer(location)
  player.device = devices[index]
  player.open()

@@ -382,7 +422,7 @@ function selectDevice (index) {

 // Stops casting, move video back to local screen
 function stop () {
-  var player = getPlayer()
+  const player = getPlayer()
  if (player) {
    player.stop(function () {
      player.device = null
@@ -417,18 +457,18 @@ function getPlayer (location) {
 }

 function play () {
-  var player = getPlayer()
+  const player = getPlayer()
  if (player) player.play(castCallback)
 }

 function pause () {
-  var player = getPlayer()
+  const player = getPlayer()
  if (player) player.pause(castCallback)
 }

 function setRate (rate) {
-  var player
-  var result = true
+  let player
+  let result = true
  if (state.playing.location === 'chromecast') {
    // TODO find how to control playback rate on chromecast
    castCallback()
@@ -443,12 +483,12 @@ function setRate (rate) {
 }

 function seek (time) {
-  var player = getPlayer()
+  const player = getPlayer()
  if (player) player.seek(time, castCallback)
 }

 function setVolume (volume) {
-  var player = getPlayer()
+  const player = getPlayer()
  if (player) player.volume(volume, castCallback)
 }

--- a/src/renderer/lib/dispatcher.js
+++ b/src/renderer/lib/dispatcher.js
@@ -4,8 +4,8 @@ module.exports = {
  setDispatch
 }

-var dispatchers = {}
-var _dispatch = function () {}
+const dispatchers = {}
+let _dispatch = function () {}

 function setDispatch (dispatch) {
  _dispatch = dispatch
@@ -20,8 +20,8 @@ function dispatch (...args) {
 // function. This prevents React from updating the listener functions on
 // each update().
 function dispatcher (...args) {
-  var str = JSON.stringify(args)
-  var handler = dispatchers[str]
+  const str = JSON.stringify(args)
+  let handler = dispatchers[str]
  if (!handler) {
    handler = dispatchers[str] = function (e) {
      // Do not propagate click to elements below the button
--- a/src/renderer/lib/errors.js
+++ b/src/renderer/lib/errors.js
@@ -1,8 +1,41 @@
-module.exports = {
-  UnplayableError
+const ExtendableError = require('es6-error')
+
+/* Generic errors */
+
+class CastingError extends ExtendableError {}
+class PlaybackError extends ExtendableError {}
+class SoundError extends ExtendableError {}
+class TorrentError extends ExtendableError {}
+
+/* Playback */
+
+class UnplayableTorrentError extends PlaybackError {
+  constructor () { super('Can\'t play any files in torrent') }
 }

-function UnplayableError () {
-  this.message = 'Can\'t play any files in torrent'
+class UnplayableFileError extends PlaybackError {
+  constructor () { super('Can\'t play that file') }
+}
+
+/* Sound */
+
+class InvalidSoundNameError extends SoundError {
+  constructor (name) { super(`Invalid sound name: ${name}`) }
+}
+
+/* Torrent */
+
+class TorrentKeyNotFoundError extends TorrentError {
+  constructor (torrentKey) { super(`Can't resolve torrent key ${torrentKey}`) }
+}
+
+module.exports = {
+  CastingError,
+  PlaybackError,
+  SoundError,
+  TorrentError,
+  UnplayableTorrentError,
+  UnplayableFileError,
+  InvalidSoundNameError,
+  TorrentKeyNotFoundError
 }
-UnplayableError.prototype = Error
--- a/src/renderer/lib/migrations.js
+++ b/src/renderer/lib/migrations.js
@@ -4,10 +4,11 @@ module.exports = {
  run
 }

-const semver = require('semver')
-const config = require('../../config')
-const TorrentSummary = require('./torrent-summary')
 const fs = require('fs')
+const path = require('path')
+const semver = require('semver')
+
+const config = require('../../config')

 // Change `state.saved` (which will be saved back to config.json on exit) as
 // needed, for example to deal with config.json format changes across versions
@@ -17,34 +18,27 @@ function run (state) {
    state.saved.version = '0.0.0' // Pre-0.7.0 version, so run all migrations
  }

-  var version = state.saved.version
+  const version = state.saved.version
+  const saved = state.saved

-  if (semver.lt(version, '0.7.0')) {
-    migrate_0_7_0(state.saved)
-  }
-
-  if (semver.lt(version, '0.7.2')) {
-    migrate_0_7_2(state.saved)
-  }
-
-  if (semver.lt(version, '0.11.0')) {
-    migrate_0_11_0(state.saved)
-  }
-
-  if (semver.lt(version, '0.12.0')) {
-    migrate_0_12_0(state.saved)
-  }
+  if (semver.lt(version, '0.7.0')) migrate_0_7_0(saved)
+  if (semver.lt(version, '0.7.2')) migrate_0_7_2(saved)
+  if (semver.lt(version, '0.11.0')) migrate_0_11_0(saved)
+  if (semver.lt(version, '0.12.0')) migrate_0_12_0(saved)
+  if (semver.lt(version, '0.14.0')) migrate_0_14_0(saved)
+  if (semver.lt(version, '0.17.0')) migrate_0_17_0(saved)
+  if (semver.lt(version, '0.17.2')) migrate_0_17_2(saved)

  // Config is now on the new version
  state.saved.version = config.APP_VERSION
 }

 function migrate_0_7_0 (saved) {
-  var fs = require('fs-extra')
-  var path = require('path')
+  const cpFile = require('cp-file')
+  const path = require('path')

  saved.torrents.forEach(function (ts) {
-    var infoHash = ts.infoHash
+    const infoHash = ts.infoHash

    // Replace torrentPath with torrentFileName
    // There are a number of cases to handle here:
@@ -52,7 +46,7 @@ function migrate_0_7_0 (saved) {
    // * Then, relative paths for the default torrents, eg '../static/sintel.torrent'
    // * Then, paths computed at runtime for default torrents, eg 'sintel.torrent'
    // * Finally, now we're getting rid of torrentPath altogether
-    var src, dst
+    let src, dst
    if (ts.torrentPath) {
      if (path.isAbsolute(ts.torrentPath) || ts.torrentPath.startsWith('..')) {
        src = ts.torrentPath
@@ -62,7 +56,7 @@ function migrate_0_7_0 (saved) {
      dst = path.join(config.TORRENT_PATH, infoHash + '.torrent')
      // Synchronous FS calls aren't ideal, but probably OK in a migration
      // that only runs once
-      if (src !== dst) fs.copySync(src, dst)
+      if (src !== dst) cpFile.sync(src, dst)

      delete ts.torrentPath
      ts.torrentFileName = infoHash + '.torrent'
@@ -70,14 +64,14 @@ function migrate_0_7_0 (saved) {

    // Replace posterURL with posterFileName
    if (ts.posterURL) {
-      var extension = path.extname(ts.posterURL)
+      const extension = path.extname(ts.posterURL)
      src = path.isAbsolute(ts.posterURL)
        ? ts.posterURL
        : path.join(config.STATIC_PATH, ts.posterURL)
      dst = path.join(config.POSTER_PATH, infoHash + extension)
      // Synchronous FS calls aren't ideal, but probably OK in a migration
      // that only runs once
-      if (src !== dst) fs.copySync(src, dst)
+      if (src !== dst) cpFile.sync(src, dst)

      delete ts.posterURL
      ts.posterFileName = infoHash + extension
@@ -108,6 +102,8 @@ function migrate_0_11_0 (saved) {
 }

 function migrate_0_12_0 (saved) {
+  const TorrentSummary = require('./torrent-summary')
+
  if (saved.prefs.openExternalPlayer == null && saved.prefs.playInVlc != null) {
    saved.prefs.openExternalPlayer = saved.prefs.playInVlc
  }
@@ -116,7 +112,7 @@ function migrate_0_12_0 (saved) {
  // Undo a terrible bug where clicking Play on a default torrent on a fresh
  // install results in a "path missing" error
  // See https://github.com/feross/webtorrent-desktop/pull/806
-  var defaultTorrentFiles = [
+  const defaultTorrentFiles = [
    '6a9759bffd5c0af65319979fb7832189f4f3c35d.torrent',
    '88594aaacbde40ef3e2510c47374ec0aa396c08e.torrent',
    '6a02592d2bbc069628cd5ed8a54f88ee06ac0ba5.torrent',
@@ -125,13 +121,88 @@ function migrate_0_12_0 (saved) {
  ]
  saved.torrents.forEach(function (torrentSummary) {
    if (!defaultTorrentFiles.includes(torrentSummary.torrentFileName)) return
-    var fileOrFolder = TorrentSummary.getFileOrFolder(torrentSummary)
+    const fileOrFolder = TorrentSummary.getFileOrFolder(torrentSummary)
    if (!fileOrFolder) return
    try {
      fs.statSync(fileOrFolder)
-    } catch (e) {
+    } catch (err) {
      // Default torrent with "missing path" error. Clear path.
      delete torrentSummary.path
    }
  })
 }
+
+function migrate_0_14_0 (saved) {
+  saved.torrents.forEach(function (ts) {
+    delete ts.defaultPlayFileIndex
+  })
+}
+
+function migrate_0_17_0 (saved) {
+  // Fix a sad, sad bug that resulted in 100MB+ config.json files
+  saved.torrents.forEach(function (ts) {
+    if (!ts.files) return
+    ts.files.forEach(function (file) {
+      if (!file.audioInfo || !file.audioInfo.picture) return
+      // This contained a Buffer, which 30x'd in size when serialized to JSON
+      delete file.audioInfo.picture
+    })
+  })
+}
+
+function migrate_0_17_2 (saved) {
+  // Remove the trailing dot (.) from the Wired CD torrent name, since
+  // folders/files that end in a trailing dot (.) or space are not deletable from
+  // Windows Explorer. See: https://github.com/feross/webtorrent-desktop/issues/905
+
+  const cpFile = require('cp-file')
+  const rimraf = require('rimraf')
+
+  const OLD_NAME = 'The WIRED CD - Rip. Sample. Mash. Share.'
+  const NEW_NAME = 'The WIRED CD - Rip. Sample. Mash. Share'
+
+  const OLD_HASH = '3ba219a8634bf7bae3d848192b2da75ae995589d'
+  const NEW_HASH = 'a88fda5954e89178c372716a6a78b8180ed4dad3'
+
+  const ts = saved.torrents.find((ts) => {
+    return ts.infoHash === OLD_HASH
+  })
+
+  if (!ts) return // Wired CD torrent does not exist
+
+  // New versions of WebTorrent ship with a fixed torrent file. Let's fix up the
+  // name in existing versions of WebTorrent.
+  ts.name = ts.displayName = NEW_NAME
+  ts.files.forEach((file) => {
+    file.path = file.path.replace(OLD_NAME, NEW_NAME)
+  })
+
+  // Changing the torrent name causes the info hash to change
+  ts.infoHash = NEW_HASH
+  ts.magnetURI = ts.magnetURI.replace(OLD_HASH, NEW_HASH)
+
+  try {
+    fs.renameSync(
+      path.join(config.POSTER_PATH, ts.posterFileName),
+      path.join(config.POSTER_PATH, NEW_HASH + '.jpg')
+    )
+  } catch (err) {}
+  ts.posterFileName = NEW_HASH + '.jpg'
+
+  rimraf.sync(path.join(config.TORRENT_PATH, ts.torrentFileName))
+  cpFile.sync(
+    path.join(config.STATIC_PATH, 'wiredCd.torrent'),
+    path.join(config.TORRENT_PATH, NEW_HASH + '.torrent')
+  )
+  ts.torrentFileName = NEW_HASH + '.torrent'
+
+  if (ts.path) {
+    // If torrent folder already exists on disk, try to rename it
+    try {
+      fs.renameSync(
+        path.join(ts.path, OLD_NAME),
+        path.join(ts.path, NEW_NAME)
+      )
+    } catch (err) {}
+  }
+}
--- a/src/renderer/lib/playlist.js
+++ b/src/renderer/lib/playlist.js
@@ -0,0 +1,87 @@
+module.exports = {
+  hasNext,
+  getNextIndex,
+  hasPrevious,
+  getPreviousIndex,
+  getCurrentLocalURL
+}
+
+const TorrentSummary = require('./torrent-summary')
+const TorrentPlayer = require('./torrent-player')
+
+const cache = {
+  infoHash: null,
+  previousIndex: null,
+  currentIndex: null,
+  nextIndex: null
+}
+
+function hasNext (state) {
+  updateCache(state)
+  return cache.nextIndex !== null
+}
+
+function getNextIndex (state) {
+  updateCache(state)
+  return cache.nextIndex
+}
+
+function hasPrevious (state) {
+  updateCache(state)
+  return cache.previousIndex !== null
+}
+
+function getPreviousIndex (state) {
+  updateCache(state)
+  return cache.previousIndex
+}
+
+function getCurrentLocalURL (state) {
+  return state.server
+    ? state.server.localURL + '/' + state.playing.fileIndex
+    : ''
+}
+
+function updateCache (state) {
+  const infoHash = state.playing.infoHash
+  const fileIndex = state.playing.fileIndex
+
+  if (infoHash === cache.infoHash) {
+    switch (fileIndex) {
+      case cache.currentIndex:
+        return
+      case cache.nextIndex:
+        cache.previousIndex = cache.currentIndex
+        cache.currentIndex = fileIndex
+        cache.nextIndex = findNextIndex(state)
+        return
+      case cache.previousIndex:
+        cache.previousIndex = findPreviousIndex(state)
+        cache.nextIndex = cache.currentIndex
+        cache.currentIndex = fileIndex
+        return
+    }
+  } else {
+    cache.infoHash = infoHash
+  }
+
+  cache.previousIndex = findPreviousIndex(state)
+  cache.currentIndex = fileIndex
+  cache.nextIndex = findNextIndex(state)
+}
+
+function findPreviousIndex (state) {
+  const files = TorrentSummary.getByKey(state, state.playing.infoHash).files
+  for (let i = state.playing.fileIndex - 1; i >= 0; i--) {
+    if (TorrentPlayer.isPlayable(files[i])) return i
+  }
+  return null
+}
+
+function findNextIndex (state) {
+  const files = TorrentSummary.getByKey(state, state.playing.infoHash).files
+  for (let i = state.playing.fileIndex + 1; i < files.length; i++) {
+    if (TorrentPlayer.isPlayable(files[i])) return i
+  }
+  return null
+}
--- a/src/renderer/lib/sound.js
+++ b/src/renderer/lib/sound.js
@@ -1,28 +1,28 @@
 module.exports = {
-  preload,
  play
 }

-var config = require('../../config')
-var path = require('path')
+const config = require('../../config')
+const {InvalidSoundNameError} = require('./errors')
+const path = require('path')

-var VOLUME = 0.15
+const VOLUME = 0.25

 /* Cache of Audio elements, for instant playback */
-var cache = {}
+const cache = {}

-var sounds = {
+const sounds = {
  ADD: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'add.wav'),
    volume: VOLUME
  },
  DELETE: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'delete.wav'),
-    volume: VOLUME
+    volume: VOLUME * 0.5
  },
  DISABLE: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'disable.wav'),
-    volume: VOLUME
+    volume: VOLUME * 0.5
  },
  DONE: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'done.wav'),
@@ -30,7 +30,7 @@ var sounds = {
  },
  ENABLE: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'enable.wav'),
-    volume: VOLUME
+    volume: VOLUME * 0.5
  },
  ERROR: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'error.wav'),
@@ -42,27 +42,16 @@ var sounds = {
  },
  STARTUP: {
    url: 'file://' + path.join(config.STATIC_PATH, 'sound', 'startup.wav'),
-    volume: VOLUME * 2
-  }
-}
-
-function preload () {
-  for (var name in sounds) {
-    if (!cache[name]) {
-      var sound = sounds[name]
-      var audio = cache[name] = new window.Audio()
-      audio.volume = sound.volume
-      audio.src = sound.url
-    }
+    volume: VOLUME
  }
 }

 function play (name) {
-  var audio = cache[name]
+  let audio = cache[name]
  if (!audio) {
-    var sound = sounds[name]
+    const sound = sounds[name]
    if (!sound) {
-      throw new Error('Invalid sound name')
+      throw new InvalidSoundNameError(name)
    }
    audio = cache[name] = new window.Audio()
    audio.volume = sound.volume
--- a/src/renderer/lib/state.js
+++ b/src/renderer/lib/state.js
@@ -1,21 +1,30 @@
-var appConfig = require('application-config')('WebTorrent')
-var path = require('path')
-var {EventEmitter} = require('events')
+const appConfig = require('application-config')('WebTorrent')
+const path = require('path')
+const {EventEmitter} = require('events')

-var config = require('../../config')
-var migrations = require('./migrations')
+const config = require('../../config')

-var State = module.exports = Object.assign(new EventEmitter(), {
-  getDefaultPlayState,
-  load,
-  save,
-  saveThrottled
-})
+const SAVE_DEBOUNCE_INTERVAL = 1000

 appConfig.filePath = path.join(config.CONFIG_PATH, 'config.json')

+const State = module.exports = Object.assign(new EventEmitter(), {
+  getDefaultPlayState,
+  load,
+  // state.save() calls are rate-limited. Use state.saveImmediate() to skip limit.
+  save: function () {
+    // Perf optimization: Lazy-require debounce (and it's dependencies)
+    const debounce = require('debounce')
+    // After first State.save() invokation, future calls go straight to the
+    // debounced function
+    State.save = debounce(saveImmediate, SAVE_DEBOUNCE_INTERVAL)
+    State.save(...arguments)
+  },
+  saveImmediate
+})
+
 function getDefaultState () {
-  var LocationHistory = require('location-history')
+  const LocationHistory = require('location-history')

  return {
    /*
@@ -68,7 +77,9 @@ function getDefaultState () {
     * Getters, for convenience
     */
    getPlayingTorrentSummary,
-    getPlayingFileSummary
+    getPlayingFileSummary,
+    getExternalPlayerName,
+    shouldHidePlayerControls
  }
 }

@@ -81,6 +92,7 @@ function getDefaultPlayState () {
    type: null, /* 'audio' or 'video', could be 'other' if ever support eg streaming to VLC */
    currentTime: 0, /* seconds */
    duration: 1, /* seconds */
+    isReady: false,
    isPaused: true,
    isStalled: false,
    lastTimeUpdate: 0, /* Unix time in ms */
@@ -97,39 +109,40 @@ function getDefaultPlayState () {
 }

 /* If the saved state file doesn't exist yet, here's what we use instead */
-function setupSavedState (cb) {
-  var fs = require('fs-extra')
-  var parseTorrent = require('parse-torrent')
-  var parallel = require('run-parallel')
+function setupStateSaved (cb) {
+  const cpFile = require('cp-file')
+  const fs = require('fs')
+  const parseTorrent = require('parse-torrent')
+  const parallel = require('run-parallel')

-  var saved = {
+  const saved = {
    prefs: {
      downloadPath: config.DEFAULT_DOWNLOAD_PATH,
      isFileHandler: false,
      openExternalPlayer: false,
-      externalPlayerPath: null
+      externalPlayerPath: null,
+      startup: false
    },
    torrents: config.DEFAULT_TORRENTS.map(createTorrentObject),
+    torrentsToResume: [],
    version: config.APP_VERSION /* make sure we can upgrade gracefully later */
  }

-  var tasks = []
+  const tasks = []

  config.DEFAULT_TORRENTS.map(function (t, i) {
-    var infoHash = saved.torrents[i].infoHash
+    const infoHash = saved.torrents[i].infoHash
    tasks.push(function (cb) {
-      fs.copy(
+      cpFile(
        path.join(config.STATIC_PATH, t.posterFileName),
-        path.join(config.POSTER_PATH, infoHash + path.extname(t.posterFileName)),
-        cb
-      )
+        path.join(config.POSTER_PATH, infoHash + path.extname(t.posterFileName))
+      ).then(cb).catch(cb)
    })
    tasks.push(function (cb) {
-      fs.copy(
+      cpFile(
        path.join(config.STATIC_PATH, t.torrentFileName),
-        path.join(config.TORRENT_PATH, infoHash + '.torrent'),
-        cb
-      )
+        path.join(config.TORRENT_PATH, infoHash + '.torrent')
+      ).then(cb).catch(cb)
    })
  })

@@ -139,8 +152,9 @@ function setupSavedState (cb) {
  })

  function createTorrentObject (t) {
-    var torrent = fs.readFileSync(path.join(config.STATIC_PATH, t.torrentFileName))
-    var parsedTorrent = parseTorrent(torrent)
+    // TODO: Doing several fs.readFileSync calls during first startup is not ideal
+    const torrent = fs.readFileSync(path.join(config.STATIC_PATH, t.torrentFileName))
+    const parsedTorrent = parseTorrent(torrent)

    return {
      status: 'paused',
@@ -151,62 +165,80 @@ function setupSavedState (cb) {
      torrentFileName: parsedTorrent.infoHash + '.torrent',
      magnetURI: parseTorrent.toMagnetURI(parsedTorrent),
      files: parsedTorrent.files,
-      selections: parsedTorrent.files.map((x) => true)
+      selections: parsedTorrent.files.map((x) => true),
+      testID: t.testID
    }
  }
 }

 function getPlayingTorrentSummary () {
-  var infoHash = this.playing.infoHash
+  const infoHash = this.playing.infoHash
  return this.saved.torrents.find((x) => x.infoHash === infoHash)
 }

 function getPlayingFileSummary () {
-  var torrentSummary = this.getPlayingTorrentSummary()
+  const torrentSummary = this.getPlayingTorrentSummary()
  if (!torrentSummary) return null
  return torrentSummary.files[this.playing.fileIndex]
 }

-function load (cb) {
-  var state = getDefaultState()
+function getExternalPlayerName () {
+  const playerPath = this.saved.prefs.externalPlayerPath
+  if (!playerPath) return 'VLC'
+  return path.basename(playerPath).split('.')[0]
+}

+function shouldHidePlayerControls () {
+  return this.location.url() === 'player' &&
+    this.playing.mouseStationarySince !== 0 &&
+    new Date().getTime() - this.playing.mouseStationarySince > 2000 &&
+    !this.playing.mouseInControls &&
+    !this.playing.isPaused &&
+    this.playing.location === 'local' &&
+    this.playing.playbackRate === 1
+}
+
+function load (cb) {
  appConfig.read(function (err, saved) {
    if (err || !saved.version) {
      console.log('Missing config file: Creating new one')
-      setupSavedState(onSaved)
+      setupStateSaved(onSavedState)
    } else {
-      onSaved(null, saved)
+      onSavedState(null, saved)
    }
  })

-  function onSaved (err, saved) {
+  function onSavedState (err, saved) {
    if (err) return cb(err)
+    const state = getDefaultState()
    state.saved = saved
-    migrations.run(state)
+
+    if (process.type === 'renderer') {
+      // Perf optimization: Save require() calls in the main process
+      const migrations = require('./migrations')
+      migrations.run(state)
+    }
+
    cb(null, state)
  }
 }

 // Write state.saved to the JSON state file
-function save (state, cb) {
+function saveImmediate (state, cb) {
  console.log('Saving state to ' + appConfig.filePath)
-  delete state.saveStateTimeout

  // Clean up, so that we're not saving any pending state
-  var copy = Object.assign({}, state.saved)
+  const copy = Object.assign({}, state.saved)
  // Remove torrents pending addition to the list, where we haven't finished
  // reading the torrent file or file(s) to seed & don't have an infohash
  copy.torrents = copy.torrents
    .filter((x) => x.infoHash)
    .map(function (x) {
-      var torrent = {}
-      for (var key in x) {
+      const torrent = {}
+      for (let key in x) {
        if (key === 'progress' || key === 'torrentKey') {
          continue // Don't save progress info or key for the webtorrent process
        }
-        if (key === 'playStatus') {
-          continue // Don't save whether a torrent is playing / pending
-        }
        if (key === 'error') {
          continue // Don't save error states
        }
@@ -217,15 +249,6 @@ function save (state, cb) {

  appConfig.write(copy, (err) => {
    if (err) console.error(err)
-    else State.emit('savedState')
+    else State.emit('stateSaved')
  })
 }
-
-// Write, but no more than once a second
-function saveThrottled (state) {
-  if (state.saveStateTimeout) return
-  state.saveStateTimeout = setTimeout(function () {
-    if (!state.saveStateTimeout) return
-    save(state)
-  }, 1000)
-}
--- a/src/renderer/lib/telemetry.js
+++ b/src/renderer/lib/telemetry.js
@@ -2,44 +2,62 @@
 // Reports back so that we can improve WebTorrent Desktop
 module.exports = {
  init,
+  send,
  logUncaughtError,
  logPlayAttempt
 }

-const crypto = require('crypto')
 const electron = require('electron')
-const https = require('https')
-const os = require('os')
-const url = require('url')

 const config = require('../../config')

-var telemetry
+let telemetry

 function init (state) {
  telemetry = state.saved.telemetry
+
+  // First app run
  if (!telemetry) {
-    telemetry = state.saved.telemetry = createSummary()
+    const crypto = require('crypto')
+    telemetry = state.saved.telemetry = {
+      userID: crypto.randomBytes(32).toString('hex') // 256-bit random ID
+    }
    reset()
  }
+}

-  var now = new Date()
+function send (state) {
+  const now = new Date()
  telemetry.version = config.APP_VERSION
  telemetry.timestamp = now.toISOString()
  telemetry.localTime = now.toTimeString()
  telemetry.screens = getScreenInfo()
  telemetry.system = getSystemInfo()
-  telemetry.approxNumTorrents = getApproxNumTorrents(state)
+  telemetry.torrentStats = getTorrentStats(state)
+  telemetry.approxNumTorrents = telemetry.torrentStats.approxCount

-  if (config.IS_PRODUCTION) {
-    postToServer()
-    // If the user keeps WebTorrent running for a long time, post every 12h
-    setInterval(postToServer, 12 * 3600 * 1000)
-  } else {
+  if (!config.IS_PRODUCTION) {
    // Development: telemetry used only for local debugging
    // Empty uncaught errors, etc at the start of every run
-    reset()
+    return reset()
  }
+
+  const get = require('simple-get')
+
+  const opts = {
+    url: config.TELEMETRY_URL,
+    body: telemetry,
+    json: true
+  }
+
+  get.post(opts, function (err, res) {
+    if (err) return console.error('Error sending telemetry', err)
+    if (res.statusCode !== 200) {
+      return console.error(`Error sending telemetry, status code: ${res.statusCode}`)
+    }
+    console.log('Sent telemetry')
+    reset()
+  })
 }

 function reset () {
@@ -48,47 +66,12 @@ function reset () {
    minVersion: config.APP_VERSION,
    total: 0,
    success: 0,
-    timeout: 0,
    error: 0,
+    external: 0,
    abandoned: 0
  }
 }

-function postToServer () {
-  // Serialize the telemetry summary
-  var payload = new Buffer(JSON.stringify(telemetry), 'utf8')
-
-  // POST to our server
-  var options = url.parse(config.TELEMETRY_URL)
-  options.method = 'POST'
-  options.headers = {
-    'Content-Type': 'application/json',
-    'Content-Length': payload.length
-  }
-
-  var req = https.request(options, function (res) {
-    if (res.statusCode === 200) {
-      console.log('Successfully posted telemetry summary')
-      reset()
-    } else {
-      console.error('Couldn\'t post telemetry summary, got HTTP ' + res.statusCode)
-    }
-  })
-  req.on('error', function (e) {
-    console.error('Couldn\'t post telemetry summary', e)
-  })
-  req.write(payload)
-  req.end()
-}
-
-// Creates a new telemetry summary. Gives the user a unique ID,
-// collects screen resolution, etc
-function createSummary () {
-  // Make a 256-bit random unique ID
-  var userID = crypto.randomBytes(32).toString('hex')
-  return { userID }
-}
-
 // Track screen resolution
 function getScreenInfo () {
  return electron.screen.getAllDisplays().map((screen) => ({
@@ -100,22 +83,69 @@ function getScreenInfo () {

 // Track basic system info like OS version and amount of RAM
 function getSystemInfo () {
+  const os = require('os')
  return {
    osPlatform: process.platform,
    osRelease: os.type() + ' ' + os.release(),
    architecture: os.arch(),
-    totalMemoryMB: os.totalmem() / (1 << 20),
+    systemArchitecture: config.OS_SYSARCH,
+    totalMemoryMB: roundPow2(os.totalmem() / (1 << 20)),
    numCores: os.cpus().length
  }
 }

-// Get the number of torrents, rounded to the nearest power of two
-function getApproxNumTorrents (state) {
-  var exactNum = state.saved.torrents.length
-  if (exactNum === 0) return 0
+// Get stats like the # of torrents currently active, # in list, total size
+function getTorrentStats (state) {
+  const count = state.saved.torrents.length
+  let sizeMB = 0
+  let byStatus = {
+    new: { count: 0, sizeMB: 0 },
+    downloading: { count: 0, sizeMB: 0 },
+    seeding: { count: 0, sizeMB: 0 },
+    paused: { count: 0, sizeMB: 0 }
+  }
+
+  // First, count torrents & total file size
+  for (let i = 0; i < count; i++) {
+    const t = state.saved.torrents[i]
+    const stat = byStatus[t.status]
+    if (!t || !t.files || !stat) continue
+    stat.count++
+    for (let j = 0; j < t.files.length; j++) {
+      const f = t.files[j]
+      if (!f || !f.length) continue
+      const fileSizeMB = f.length / (1 << 20)
+      sizeMB += fileSizeMB
+      stat.sizeMB += fileSizeMB
+    }
+  }
+
+  // Then, round all the counts and sums to the nearest power of 2
+  const ret = roundTorrentStats({count, sizeMB})
+  ret.byStatus = {
+    new: roundTorrentStats(byStatus.new),
+    downloading: roundTorrentStats(byStatus.downloading),
+    seeding: roundTorrentStats(byStatus.seeding),
+    paused: roundTorrentStats(byStatus.paused)
+  }
+  return ret
+}
+
+function roundTorrentStats (stats) {
+  return {
+    approxCount: roundPow2(stats.count),
+    approxSizeMB: roundPow2(stats.sizeMB)
+  }
+}
+
+// Rounds to the nearest power of 2, for privacy and easy bucketing.
+// Rounds 35 to 32, 70 to 64, 5 to 4, 1 to 1, 0 to 0.
+// Supports nonnegative numbers only.
+function roundPow2 (n) {
+  if (n <= 0) return 0
  // Otherwise, return 1, 2, 4, 8, etc by rounding in log space
-  var log2 = Math.log(exactNum) / Math.log(2)
-  return 1 << Math.round(log2)
+  const log2 = Math.log(n) / Math.log(2)
+  return Math.pow(2, Math.round(log2))
 }

 // An uncaught error happened in the main process or in one of the windows
@@ -124,12 +154,10 @@ function logUncaughtError (procName, e) {
  // Hopefully uncaught errors immediately on startup are fixed in dev
  if (!telemetry) return

-  var message
-  var stack = ''
-  if (e.message) {
-    // err is either an Error or a plain object {message, stack}
-    message = e.message
-    stack = e.stack
+  let message
+  let stack = ''
+  if (e == null) {
+    message = 'Unexpected undefined error'
  } else if (e.error) {
    // Uncaught Javascript errors (window.onerror), err is an ErrorEvent
    if (!e.error.message) {
@@ -138,6 +166,10 @@ function logUncaughtError (procName, e) {
      message = e.error.message
      stack = e.error.stack
    }
+  } else if (e.message) {
+    // err is either an Error or a plain object {message, stack}
+    message = e.message
+    stack = e.stack
  } else {
    // Resource errors (captured element.onerror), err is an Event
    if (!e.target) {
@@ -149,11 +181,14 @@ function logUncaughtError (procName, e) {
    }
  }

+  if (typeof stack !== 'string') stack = 'Unexpected stack: ' + stack
+  if (typeof message !== 'string') message = 'Unexpected message: ' + message
+
  // Remove the first part of each file path in the stack trace.
  // - Privacy: remove personal info like C:\Users\<full name>
  // - Aggregation: this lets us find which stacktraces occur often
-  if (stack && typeof stack === 'string') stack = stack.replace(/\(.*app.asar/g, '(...')
-  else if (stack) stack = 'Unexpected stack: ' + stack
+  stack = stack.replace(/\(.*app.asar/g, '(...')
+  stack = stack.replace(/at .*app.asar/g, 'at ...')

  // We need to POST the telemetry object, make sure it stays < 100kb
  if (telemetry.uncaughtErrors.length > 20) return
@@ -161,28 +196,28 @@ function logUncaughtError (procName, e) {
  if (stack.length > 1000) stack = stack.substring(0, 1000)

  // Log the app version *at the time of the error*
-  var version = config.APP_VERSION
+  const version = config.APP_VERSION

  telemetry.uncaughtErrors.push({process: procName, message, stack, version})
 }

 // Turns a DOM element into a string, eg "DIV.my-class.visible"
 function getElemString (elem) {
-  var ret = elem.tagName
+  let ret = elem.tagName
  try {
    ret += '.' + Array.from(elem.classList).join('.')
-  } catch (e) {}
+  } catch (err) {}
  return ret
 }

-// The user pressed play. It either worked, timed out, or showed the
-// 'Play in VLC' codec error
+// The user pressed play. Did it work, display an error,
+// open an external player or did user abandon the attempt?
 function logPlayAttempt (result) {
-  if (!['success', 'timeout', 'error', 'abandoned'].includes(result)) {
+  if (!['success', 'error', 'external', 'abandoned'].includes(result)) {
    return console.error('Unknown play attempt result', result)
  }

-  var attempts = telemetry.playAttempts
+  const attempts = telemetry.playAttempts
  attempts.total = (attempts.total || 0) + 1
  attempts[result] = (attempts[result] || 0) + 1
 }
--- a/src/renderer/lib/torrent-player.js
+++ b/src/renderer/lib/torrent-player.js
@@ -3,11 +3,10 @@ module.exports = {
  isVideo,
  isAudio,
  isTorrent,
-  isPlayableTorrentSummary,
-  pickFileToPlay
+  isPlayableTorrentSummary
 }

-var path = require('path')
+const path = require('path')

 // Checks whether a fileSummary or file path is audio/video that we can play,
 // based on the file extension
@@ -38,6 +37,7 @@ function isAudio (file) {
    '.mp3',
    '.ogg',
    '.wav',
+    '.flac',
    '.m4a'
  ].includes(getFileExtension(file))
 }
@@ -47,38 +47,16 @@ function isAudio (file) {
 // - a file object where obj.name is ends in .torrent
 // - a string that's a magnet link (magnet://...)
 function isTorrent (file) {
-  var isTorrentFile = getFileExtension(file) === '.torrent'
-  var isMagnet = typeof file === 'string' && /^(stream-)?magnet:/.test(file)
+  const isTorrentFile = getFileExtension(file) === '.torrent'
+  const isMagnet = typeof file === 'string' && /^(stream-)?magnet:/.test(file)
  return isTorrentFile || isMagnet
 }

 function getFileExtension (file) {
-  var name = typeof file === 'string' ? file : file.name
+  const name = typeof file === 'string' ? file : file.name
  return path.extname(name).toLowerCase()
 }

 function isPlayableTorrentSummary (torrentSummary) {
  return torrentSummary.files && torrentSummary.files.some(isPlayable)
 }
-
-// Picks the default file to play from a list of torrent or torrentSummary files
-// Returns an index or undefined, if no files are playable
-function pickFileToPlay (files) {
-  // first, try to find the biggest video file
-  var videoFiles = files.filter(isVideo)
-  if (videoFiles.length > 0) {
-    var largestVideoFile = videoFiles.reduce(function (a, b) {
-      return a.length > b.length ? a : b
-    })
-    return files.indexOf(largestVideoFile)
-  }
-
-  // if there are no videos, play the first audio file
-  var audioFiles = files.filter(isAudio)
-  if (audioFiles.length > 0) {
-    return files.indexOf(audioFiles[0])
-  }
-
-  // no video or audio means nothing is playable
-  return undefined
-}
--- a/src/renderer/lib/torrent-poster.js
+++ b/src/renderer/lib/torrent-poster.js
@@ -1,22 +1,22 @@
 module.exports = torrentPoster

-var captureVideoFrame = require('./capture-video-frame')
-var path = require('path')
+const captureFrame = require('capture-frame')
+const path = require('path')

 function torrentPoster (torrent, cb) {
  // First, try to use a poster image if available
-  var posterFile = torrent.files.filter(function (file) {
+  const posterFile = torrent.files.filter(function (file) {
    return /^poster\.(jpg|png|gif)$/.test(file.name)
  })[0]
  if (posterFile) return torrentPosterFromImage(posterFile, torrent, cb)

  // Second, try to use the largest video file
  // Filter out file formats that the <video> tag definitely can't play
-  var videoFile = getLargestFileByExtension(torrent, ['.mp4', '.m4v', '.webm', '.mov', '.mkv'])
+  const videoFile = getLargestFileByExtension(torrent, ['.mp4', '.m4v', '.webm', '.mov', '.mkv'])
  if (videoFile) return torrentPosterFromVideo(videoFile, torrent, cb)

  // Third, try to use the largest image file
-  var imgFile = getLargestFileByExtension(torrent, ['.gif', '.jpg', '.jpeg', '.png'])
+  const imgFile = getLargestFileByExtension(torrent, ['.gif', '.jpg', '.jpeg', '.png'])
  if (imgFile) return torrentPosterFromImage(imgFile, torrent, cb)

  // TODO: generate a waveform from the largest sound file
@@ -25,8 +25,8 @@ function torrentPoster (torrent, cb) {
 }

 function getLargestFileByExtension (torrent, extensions) {
-  var files = torrent.files.filter(function (file) {
-    var extname = path.extname(file.name).toLowerCase()
+  const files = torrent.files.filter(function (file) {
+    const extname = path.extname(file.name).toLowerCase()
    return extensions.indexOf(extname) !== -1
  })
  if (files.length === 0) return undefined
@@ -36,15 +36,15 @@ function getLargestFileByExtension (torrent, extensions) {
 }

 function torrentPosterFromVideo (file, torrent, cb) {
-  var index = torrent.files.indexOf(file)
+  const index = torrent.files.indexOf(file)

-  var server = torrent.createServer(0)
+  const server = torrent.createServer(0)
  server.listen(0, onListening)

  function onListening () {
-    var port = server.address().port
-    var url = 'http://localhost:' + port + '/' + index
-    var video = document.createElement('video')
+    const port = server.address().port
+    const url = 'http://localhost:' + port + '/' + index
+    const video = document.createElement('video')
    video.addEventListener('canplay', onCanPlay)

    video.volume = 0
@@ -61,7 +61,7 @@ function torrentPosterFromVideo (file, torrent, cb) {
    function onSeeked () {
      video.removeEventListener('seeked', onSeeked)

-      var buf = captureVideoFrame(video)
+      const buf = captureFrame(video)

      // unload video element
      video.pause()
@@ -78,6 +78,6 @@ function torrentPosterFromVideo (file, torrent, cb) {
 }

 function torrentPosterFromImage (file, torrent, cb) {
-  var extname = path.extname(file.name)
+  const extname = path.extname(file.name)
  file.getBuffer((err, buf) => cb(err, buf, extname))
 }
--- a/src/renderer/lib/torrent-summary.js
+++ b/src/renderer/lib/torrent-summary.js
@@ -2,12 +2,12 @@ module.exports = {
  getPosterPath,
  getTorrentPath,
  getByKey,
-  getTorrentID,
+  getTorrentId,
  getFileOrFolder
 }

-var path = require('path')
-var config = require('../../config')
+const path = require('path')
+const config = require('../../config')

 // Expects a torrentSummary
 // Returns an absolute path to the torrent file, or null if unavailable
@@ -20,7 +20,7 @@ function getTorrentPath (torrentSummary) {
 // Returns an absolute path to the poster image, or null if unavailable
 function getPosterPath (torrentSummary) {
  if (!torrentSummary || !torrentSummary.posterFileName) return null
-  var posterPath = path.join(config.POSTER_PATH, torrentSummary.posterFileName)
+  const posterPath = path.join(config.POSTER_PATH, torrentSummary.posterFileName)
  // Work around a Chrome bug (reproduced in vanilla Chrome, not just Electron):
  // Backslashes in URLS in CSS cause bizarre string encoding issues
  return posterPath.replace(/\\/g, '/')
@@ -28,8 +28,8 @@ function getPosterPath (torrentSummary) {

 // Expects a torrentSummary
 // Returns a torrentID: filename, magnet URI, or infohash
-function getTorrentID (torrentSummary) {
-  var s = torrentSummary
+function getTorrentId (torrentSummary) {
+  const s = torrentSummary
  if (s.torrentFileName) { // Load torrent file from disk
    return getTorrentPath(s)
  } else { // Load torrent from DHT
@@ -51,7 +51,8 @@ function getByKey (state, torrentKey) {
 // TODO: make this assumption explicit, enforce it in the `create-torrent`
 // module. Store root folder explicitly to avoid hacky path processing below.
 function getFileOrFolder (torrentSummary) {
-  var ts = torrentSummary
+  const ts = torrentSummary
  if (!ts.path || !ts.files || ts.files.length === 0) return null
-  return path.join(ts.path, ts.files[0].path.split('/')[0])
+  const dirname = ts.files[0].path.split(path.sep)[0]
+  return path.join(ts.path, dirname)
 }
--- a/src/renderer/main.js
+++ b/src/renderer/main.js
@@ -1,8 +1,30 @@
+/**
+ * Perf optimization: Hook into require() to modify how certain modules load:
+ *
+ * - `inline-style-prefixer` (used by `material-ui`) takes ~40ms. It is not
+ *   actually used because auto-prefixing is disabled with
+ *   `darkBaseTheme.userAgent = false`. Return a fake object.
+ */
+let Module = require('module')
+const _require = Module.prototype.require
+Module.prototype.require = function (id) {
+  if (id === 'inline-style-prefixer') return {}
+  return _require.apply(this, arguments)
+}
+
 console.time('init')

 const crashReporter = require('../crash-reporter')
 crashReporter.init()

+// Perf optimization: Start asynchronously read on config file before all the
+// blocking require() calls below.
+
+const State = require('./lib/state')
+State.load(onState)
+
+const createGetter = require('fn-getter')
+const debounce = require('debounce')
 const dragDrop = require('drag-drop')
 const electron = require('electron')
 const fs = require('fs')
@@ -12,62 +34,84 @@ const ReactDOM = require('react-dom')
 const config = require('../config')
 const telemetry = require('./lib/telemetry')
 const sound = require('./lib/sound')
-const State = require('./lib/state')
 const TorrentPlayer = require('./lib/torrent-player')

+// Perf optimization: Needed immediately, so do not lazy load it below
+const TorrentListController = require('./controllers/torrent-list-controller')
+
 // Required by Material UI -- adds `onTouchTap` event
 require('react-tap-event-plugin')()

-const App = require('./pages/App')
+const App = require('./pages/app')

-const MediaController = require('./controllers/media-controller')
-const UpdateController = require('./controllers/update-controller')
-const PrefsController = require('./controllers/prefs-controller')
-const PlaybackController = require('./controllers/playback-controller')
-const SubtitlesController = require('./controllers/subtitles-controller')
-const TorrentListController = require('./controllers/torrent-list-controller')
-const TorrentController = require('./controllers/torrent-controller')
+// Electron apps have two processes: a main process (node) runs first and starts
+// a renderer process (essentially a Chrome window). We're in the renderer process,
+// and this IPC channel receives from and sends messages to the main process
+const ipcRenderer = electron.ipcRenderer

 // Yo-yo pattern: state object lives here and percolates down thru all the views.
 // Events come back up from the views via dispatch(...)
 require('./lib/dispatcher').setDispatch(dispatch)

 // From dispatch(...), events are sent to one of the controllers
-var controllers = null
+let controllers = null

 // This dependency is the slowest-loading, so we lazy load it
-var Cast = null
-
-// Electron apps have two processes: a main process (node) runs first and starts
-// a renderer process (essentially a Chrome window). We're in the renderer process,
-// and this IPC channel receives from and sends messages to the main process
-var ipcRenderer = electron.ipcRenderer
+let Cast = null

 // All state lives in state.js. `state.saved` is read from and written to a file.
 // All other state is ephemeral. First we load state.saved then initialize the app.
-var state
+let state

 // Root React component
-var app
-
-State.load(onState)
+let app

 // Called once when the application loads. (Not once per window.)
 // Connects to the torrent networks, sets up the UI and OS integrations like
 // the dock icon and drag+drop.
 function onState (err, _state) {
  if (err) return onError(err)
-  state = window.state = _state // Make available for easier debugging
+
+  // Make available for easier debugging
+  state = window.state = _state
+  window.dispatch = dispatch
+
+  telemetry.init(state)
+
+  // Log uncaught JS errors
+  window.addEventListener(
+    'error', (e) => telemetry.logUncaughtError('window', e), true /* capture */
+  )

  // Create controllers
  controllers = {
-    media: new MediaController(state),
-    update: new UpdateController(state),
-    prefs: new PrefsController(state, config),
-    playback: new PlaybackController(state, config, update),
-    subtitles: new SubtitlesController(state),
-    torrentList: new TorrentListController(state),
-    torrent: new TorrentController(state)
+    media: createGetter(() => {
+      const MediaController = require('./controllers/media-controller')
+      return new MediaController(state)
+    }),
+    playback: createGetter(() => {
+      const PlaybackController = require('./controllers/playback-controller')
+      return new PlaybackController(state, config, update)
+    }),
+    prefs: createGetter(() => {
+      const PrefsController = require('./controllers/prefs-controller')
+      return new PrefsController(state, config)
+    }),
+    subtitles: createGetter(() => {
+      const SubtitlesController = require('./controllers/subtitles-controller')
+      return new SubtitlesController(state)
+    }),
+    torrent: createGetter(() => {
+      const TorrentController = require('./controllers/torrent-controller')
+      return new TorrentController(state)
+    }),
+    torrentList: createGetter(() => {
+      return new TorrentListController(state)
+    }),
+    update: createGetter(() => {
+      const UpdateController = require('./controllers/update-controller')
+      return new UpdateController(state)
+    })
  }

  // Add first page to location history
@@ -82,23 +126,18 @@ function onState (err, _state) {
  // Restart everything we were torrenting last time the app ran
  resumeTorrents()

+  // Initialize ReactDOM
+  app = ReactDOM.render(<App state={state} />, document.querySelector('#body'))
+
  // Calling update() updates the UI given the current state
  // Do this at least once a second to give every file in every torrentSummary
  // a progress bar and to keep the cursor in sync when playing a video
  setInterval(update, 1000)
-  app = ReactDOM.render(<App state={state} />, document.querySelector('#body'))
-
-  // Lazy-load other stuff, like the AppleTV module, later to keep startup fast
-  window.setTimeout(delayedInit, config.DELAYED_INIT)

  // Listen for messages from the main process
  setupIpc()

-  // Warn if the download dir is gone, eg b/c an external drive is unplugged
-  checkDownloadPath()
-
-  // OS integrations:
-  // ...drag and drop files/text to start torrenting or seeding
+  // Drag and drop files/text to start torrenting or seeding
  dragDrop('body', {
    onDrop: onOpen,
    onDropText: onOpen
@@ -107,28 +146,49 @@ function onState (err, _state) {
  // ...same thing if you paste a torrent
  document.addEventListener('paste', onPaste)

+  const debouncedFullscreenToggle = debounce(function () {
+    dispatch('toggleFullScreen')
+  }, 1000, true)
+
+  document.addEventListener('wheel', function (event) {
+    // ctrlKey detects pinch to zoom, http://crbug.com/289887
+    if (event.ctrlKey) {
+      event.preventDefault()
+      debouncedFullscreenToggle()
+    }
+  })
+
  // ...focus and blur. Needed to show correct dock icon text ('badge') in OSX
  window.addEventListener('focus', onFocus)
  window.addEventListener('blur', onBlur)

-  // ...window visibility state.
-  document.addEventListener('webkitvisibilitychange', onVisibilityChange)
+  if (electron.remote.getCurrentWindow().isVisible()) {
+    sound.play('STARTUP')
+  }

-  // Log uncaught JS errors
-  window.addEventListener('error',
-    (e) => telemetry.logUncaughtError('window', e),
-    true /* capture */)
+  // To keep app startup fast, some code is delayed.
+  window.setTimeout(delayedInit, config.DELAYED_INIT)

  // Done! Ideally we want to get here < 500ms after the user clicks the app
-  sound.play('STARTUP')
  console.timeEnd('init')
 }

 // Runs a few seconds after the app loads, to avoid slowing down startup time
 function delayedInit () {
+  telemetry.send(state)
+
+  // Send telemetry data every 12 hours, for users who keep the app running
+  // for extended periods of time
+  setInterval(() => telemetry.send(state), 12 * 3600 * 1000)
+
+  // Warn if the download dir is gone, eg b/c an external drive is unplugged
+  checkDownloadPath()
+
+  // ...window visibility state.
+  document.addEventListener('webkitvisibilitychange', onVisibilityChange)
+  onVisibilityChange()
+
  lazyLoadCast()
-  sound.preload()
-  telemetry.init(state)
 }

 // Lazily loads Chromecast and Airplay support
@@ -146,7 +206,7 @@ function lazyLoadCast () {
 // 3. dispatch - the event handler calls dispatch(), main.js sends it to a controller
 // 4. controller - the controller handles the event, changing the state object
 function update () {
-  controllers.playback.showOrHidePlayerControls()
+  controllers.playback().showOrHidePlayerControls()
  app.setState(state)
  updateElectron()
 }
@@ -174,44 +234,58 @@ const dispatchHandlers = {
  'openFiles': () => ipcRenderer.send('openFiles'), /* shows the open file dialog */
  'openTorrentAddress': () => { state.modal = { id: 'open-torrent-address-modal' } },

-  'addTorrent': (torrentId) => controllers.torrentList.addTorrent(torrentId),
-  'showCreateTorrent': (paths) => controllers.torrentList.showCreateTorrent(paths),
-  'createTorrent': (options) => controllers.torrentList.createTorrent(options),
-  'toggleTorrent': (infoHash) => controllers.torrentList.toggleTorrent(infoHash),
-  'toggleTorrentFile': (infoHash, index) => controllers.torrentList.toggleTorrentFile(infoHash, index),
-  'confirmDeleteTorrent': (infoHash, deleteData) => controllers.torrentList.confirmDeleteTorrent(infoHash, deleteData),
-  'deleteTorrent': (infoHash, deleteData) => controllers.torrentList.deleteTorrent(infoHash, deleteData),
-  'toggleSelectTorrent': (infoHash) => controllers.torrentList.toggleSelectTorrent(infoHash),
-  'openTorrentContextMenu': (infoHash) => controllers.torrentList.openTorrentContextMenu(infoHash),
-  'startTorrentingSummary': (torrentKey) => controllers.torrentList.startTorrentingSummary(torrentKey),
-  'pauseAllTorrents': (params) => controllers.torrentList.pauseAll(params),
-  'resumePausedTorrents': () => controllers.torrentList.resumePausedTorrents(),
+  'addTorrent': (torrentId) => controllers.torrentList().addTorrent(torrentId),
+  'showCreateTorrent': (paths) => controllers.torrentList().showCreateTorrent(paths),
+  'createTorrent': (options) => controllers.torrentList().createTorrent(options),
+  'toggleTorrent': (infoHash) => controllers.torrentList().toggleTorrent(infoHash),
+  'pauseAllTorrents': () => controllers.torrentList().pauseAllTorrents(),
+  'resumeAllTorrents': () => controllers.torrentList().resumeAllTorrents(),
+  'toggleTorrentFile': (infoHash, index) =>
+    controllers.torrentList().toggleTorrentFile(infoHash, index),
+  'confirmDeleteTorrent': (infoHash, deleteData) =>
+    controllers.torrentList().confirmDeleteTorrent(infoHash, deleteData),
+  'deleteTorrent': (infoHash, deleteData) =>
+    controllers.torrentList().deleteTorrent(infoHash, deleteData),
+  'toggleSelectTorrent': (infoHash) =>
+    controllers.torrentList().toggleSelectTorrent(infoHash),
+  'openTorrentContextMenu': (infoHash) =>
+    controllers.torrentList().openTorrentContextMenu(infoHash),
+  'startTorrentingSummary': (torrentKey) =>
+    controllers.torrentList().startTorrentingSummary(torrentKey),
+  'saveTorrentFileAs': (torrentKey) =>
+    controllers.torrentList().saveTorrentFileAs(torrentKey),
+  'prioritizeTorrent': (infoHash) => controllers.torrentList().prioritizeTorrent(infoHash),
+  'resumePausedTorrents': () => controllers.torrentList().resumePausedTorrents(),

  // Playback
-  'playFile': (infoHash, index) => controllers.playback.playFile(infoHash, index),
-  'playPause': () => controllers.playback.playPause(),
-  'skip': (time) => controllers.playback.skip(time),
-  'skipTo': (time) => controllers.playback.skipTo(time),
-  'changePlaybackRate': (dir) => controllers.playback.changePlaybackRate(dir),
-  'changeVolume': (delta) => controllers.playback.changeVolume(delta),
-  'setVolume': (vol) => controllers.playback.setVolume(vol),
-  'openItem': (infoHash, index) => controllers.playback.openItem(infoHash, index),
+  'playFile': (infoHash, index) => controllers.playback().playFile(infoHash, index),
+  'playPause': () => controllers.playback().playPause(),
+  'nextTrack': () => controllers.playback().nextTrack(),
+  'previousTrack': () => controllers.playback().previousTrack(),
+  'skip': (time) => controllers.playback().skip(time),
+  'skipTo': (time) => controllers.playback().skipTo(time),
+  'changePlaybackRate': (dir) => controllers.playback().changePlaybackRate(dir),
+  'changeVolume': (delta) => controllers.playback().changeVolume(delta),
+  'setVolume': (vol) => controllers.playback().setVolume(vol),
+  'openItem': (infoHash, index) => controllers.playback().openItem(infoHash, index),

  // Subtitles
-  'openSubtitles': () => controllers.subtitles.openSubtitles(),
-  'selectSubtitle': (index) => controllers.subtitles.selectSubtitle(index),
-  'toggleSubtitlesMenu': () => controllers.subtitles.toggleSubtitlesMenu(),
-  'checkForSubtitles': () => controllers.subtitles.checkForSubtitles(),
-  'addSubtitles': (files, autoSelect) => controllers.subtitles.addSubtitles(files, autoSelect),
+  'openSubtitles': () => controllers.subtitles().openSubtitles(),
+  'selectSubtitle': (index) => controllers.subtitles().selectSubtitle(index),
+  'toggleSubtitlesMenu': () => controllers.subtitles().toggleSubtitlesMenu(),
+  'checkForSubtitles': () => controllers.subtitles().checkForSubtitles(),
+  'addSubtitles': (files, autoSelect) => controllers.subtitles().addSubtitles(files, autoSelect),

  // Local media: <video>, <audio>, external players
-  'mediaStalled': () => controllers.media.mediaStalled(),
-  'mediaError': (err) => controllers.media.mediaError(err),
-  'mediaSuccess': () => controllers.media.mediaSuccess(),
-  'mediaTimeUpdate': () => controllers.media.mediaTimeUpdate(),
-  'mediaMouseMoved': () => controllers.media.mediaMouseMoved(),
-  'openExternalPlayer': () => controllers.media.openExternalPlayer(),
-  'externalPlayerNotFound': () => controllers.media.externalPlayerNotFound(),
+  'mediaStalled': () => controllers.media().mediaStalled(),
+  'mediaError': (err) => controllers.media().mediaError(err),
+  'mediaSuccess': () => controllers.media().mediaSuccess(),
+  'mediaTimeUpdate': () => controllers.media().mediaTimeUpdate(),
+  'mediaMouseMoved': () => controllers.media().mediaMouseMoved(),
+  'mediaControlsMouseEnter': () => controllers.media().controlsMouseEnter(),
+  'mediaControlsMouseLeave': () => controllers.media().controlsMouseLeave(),
+  'openExternalPlayer': () => controllers.media().openExternalPlayer(),
+  'externalPlayerNotFound': () => controllers.media().externalPlayerNotFound(),

  // Remote casting: Chromecast, Airplay, etc
  'toggleCastMenu': (deviceType) => lazyLoadCast().toggleMenu(deviceType),
@@ -219,13 +293,13 @@ const dispatchHandlers = {
  'stopCasting': () => lazyLoadCast().stop(),

  // Preferences screen
-  'preferences': () => controllers.prefs.show(),
-  'updatePreferences': (key, value) => controllers.prefs.update(key, value),
+  'preferences': () => controllers.prefs().show(),
+  'updatePreferences': (key, value) => controllers.prefs().update(key, value),
  'checkDownloadPath': checkDownloadPath,

  // Update (check for new versions on Linux, where there's no auto updater)
-  'updateAvailable': (version) => controllers.update.updateAvailable(version),
-  'skipVersion': (version) => controllers.update.skipVersion(version),
+  'updateAvailable': (version) => controllers.update().updateAvailable(version),
+  'skipVersion': (version) => controllers.update().skipVersion(version),

  // Navigation between screens (back, forward, ESC, etc)
  'exitModal': () => { state.modal = null },
@@ -245,8 +319,8 @@ const dispatchHandlers = {
  'onOpen': onOpen,
  'error': onError,
  'uncaughtError': (proc, err) => telemetry.logUncaughtError(proc, err),
-  'saveState': () => State.save(state),
-  'saveStateThrottled': () => State.saveThrottled(state),
+  'stateSave': () => State.save(state),
+  'stateSaveImmediate': () => State.saveImmediate(state),
  'update': () => {} // No-op, just trigger an update
 }

@@ -257,13 +331,13 @@ function dispatch (action, ...args) {
    console.log('dispatch: %s %o', action, args)
  }

-  var handler = dispatchHandlers[action]
+  const handler = dispatchHandlers[action]
  if (handler) handler(...args)
  else console.error('Missing dispatch handler: ' + action)

  // Update the virtual DOM, unless it's just a mouse move event
  if (action !== 'mediaMouseMoved' ||
-      controllers.playback.showOrHidePlayerControls()) {
+      controllers.playback().showOrHidePlayerControls()) {
    update()
  }
 }
@@ -276,8 +350,9 @@ function setupIpc () {
  ipcRenderer.on('dispatch', (e, ...args) => dispatch(...args))

  ipcRenderer.on('fullscreenChanged', onFullscreenChanged)
+  ipcRenderer.on('windowBoundsChanged', onWindowBoundsChanged)

-  var tc = controllers.torrent
+  const tc = controllers.torrent()
  ipcRenderer.on('wt-infohash', (e, ...args) => tc.torrentInfoHash(...args))
  ipcRenderer.on('wt-metadata', (e, ...args) => tc.torrentMetadata(...args))
  ipcRenderer.on('wt-done', (e, ...args) => tc.torrentDone(...args))
@@ -295,7 +370,7 @@ function setupIpc () {

  ipcRenderer.send('ipcReady')

-  State.on('savedState', () => ipcRenderer.send('savedState'))
+  State.on('stateSaved', () => ipcRenderer.send('stateSaved'))
 }

 // Quits any modal popovers and returns to the torrent list screen
@@ -304,7 +379,7 @@ function backToList () {
  state.modal = null
  state.location.backToFirst(function () {
    // If we were already on the torrent list, scroll to the top
-    var contentTag = document.querySelector('.content')
+    const contentTag = document.querySelector('.content')
    if (contentTag) contentTag.scrollTop = 0
  })
 }
@@ -330,7 +405,7 @@ function resumeTorrents () {
      return torrentSummary
    })
    .filter((s) => s.status !== 'paused')
-    .forEach((s) => controllers.torrentList.startTorrentingSummary(s.torrentKey))
+    .forEach((s) => controllers.torrentList().startTorrentingSummary(s.torrentKey))
 }

 // Set window dimensions to match video dimensions or fill the screen
@@ -351,18 +426,18 @@ function setDimensions (dimensions) {
  state.window.wasMaximized = electron.remote.getCurrentWindow().isMaximized

  // Limit window size to screen size
-  var screenWidth = window.screen.width
-  var screenHeight = window.screen.height
-  var aspectRatio = dimensions.width / dimensions.height
-  var scaleFactor = Math.min(
+  const screenWidth = window.screen.width
+  const screenHeight = window.screen.height
+  const aspectRatio = dimensions.width / dimensions.height
+  const scaleFactor = Math.min(
    Math.min(screenWidth / dimensions.width, 1),
    Math.min(screenHeight / dimensions.height, 1)
  )
-  var width = Math.max(
+  const width = Math.max(
    Math.floor(dimensions.width * scaleFactor),
    config.WINDOW_MIN_WIDTH
  )
-  var height = Math.max(
+  const height = Math.max(
    Math.floor(dimensions.height * scaleFactor),
    config.WINDOW_MIN_HEIGHT
  )
@@ -377,22 +452,22 @@ function setDimensions (dimensions) {
 function onOpen (files) {
  if (!Array.isArray(files)) files = [ files ]

-  var url = state.location.url()
-  var allTorrents = files.every(TorrentPlayer.isTorrent)
-  var allSubtitles = files.every(controllers.subtitles.isSubtitle)
+  const url = state.location.url()
+  const allTorrents = files.every(TorrentPlayer.isTorrent)
+  const allSubtitles = files.every(controllers.subtitles().isSubtitle)

  if (allTorrents) {
    // Drop torrents onto the app: go to home screen, add torrents, no matter what
    dispatch('backToList')
    // All .torrent files? Add them.
-    files.forEach((file) => controllers.torrentList.addTorrent(file))
+    files.forEach((file) => controllers.torrentList().addTorrent(file))
  } else if (url === 'player' && allSubtitles) {
    // Drop subtitles onto a playing video: add subtitles
-    controllers.subtitles.addSubtitles(files, true)
+    controllers.subtitles().addSubtitles(files, true)
  } else if (url === 'home') {
    // Drop files onto home screen: show Create Torrent
    state.modal = null
-    controllers.torrentList.showCreateTorrent(files)
+    controllers.torrentList().showCreateTorrent(files)
  } else {
    // Drop files onto any other screen: show error
    return onError('Please go back to the torrent list before creating a new torrent.')
@@ -412,15 +487,11 @@ function onError (err) {
  update()
 }

-function onPaste (e) {
-  if (e.target.tagName.toLowerCase() === 'input') return
+const editableHtmlTags = new Set(['input', 'textarea'])

-  var torrentIds = electron.clipboard.readText().split('\n')
-  torrentIds.forEach(function (torrentId) {
-    torrentId = torrentId.trim()
-    if (torrentId.length === 0) return
-    controllers.torrentList.addTorrent(torrentId)
-  })
+function onPaste (e) {
+  if (editableHtmlTags.has(e.target.tagName.toLowerCase())) return
+  controllers.torrentList().addTorrent(electron.clipboard.readText())

  update()
 }
@@ -450,6 +521,13 @@ function onFullscreenChanged (e, isFullScreen) {
  update()
 }

+function onWindowBoundsChanged (e, newBounds) {
+  if (state.location.url() !== 'player') {
+    state.saved.bounds = newBounds
+    dispatch('stateSave')
+  }
+}
+
 function checkDownloadPath () {
  fs.stat(state.saved.prefs.downloadPath, function (err, stat) {
    if (err) {
--- a/src/renderer/pages/App.js
+++ b/src/renderer/pages/App.js
@@ -1,111 +0,0 @@
-const colors = require('material-ui/styles/colors')
-const React = require('react')
-
-const darkBaseTheme = require('material-ui/styles/baseThemes/darkBaseTheme').default
-const getMuiTheme = require('material-ui/styles/getMuiTheme').default
-const MuiThemeProvider = require('material-ui/styles/MuiThemeProvider').default
-
-const Header = require('../components/Header')
-
-const Views = {
-  'home': require('./TorrentListPage'),
-  'player': require('./PlayerPage'),
-  'create-torrent': require('./CreateTorrentPage'),
-  'preferences': require('./PreferencesPage')
-}
-
-const Modals = {
-  'open-torrent-address-modal': require('../components/open-torrent-address-modal'),
-  'remove-torrent-modal': require('../components/remove-torrent-modal'),
-  'update-available-modal': require('../components/update-available-modal'),
-  'unsupported-media-modal': require('../components/unsupported-media-modal')
-}
-
-darkBaseTheme.fontFamily = process.platform === 'win32'
-  ? '"Segoe UI", sans-serif'
-  : 'BlinkMacSystemFont, "Helvetica Neue", Helvetica, sans-serif'
-darkBaseTheme.palette.primary1Color = colors.cyan500
-darkBaseTheme.palette.primary2Color = colors.cyan500
-darkBaseTheme.palette.primary3Color = colors.grey600
-darkBaseTheme.palette.accent1Color = colors.redA200
-darkBaseTheme.palette.accent2Color = colors.redA400
-darkBaseTheme.palette.accent3Color = colors.redA100
-
-class App extends React.Component {
-  render () {
-    var state = this.props.state
-
-    // Hide player controls while playing video, if the mouse stays still for a while
-    // Never hide the controls when:
-    // * The mouse is over the controls or we're scrubbing (see CSS)
-    // * The video is paused
-    // * The video is playing remotely on Chromecast or Airplay
-    var hideControls = state.location.url() === 'player' &&
-      state.playing.mouseStationarySince !== 0 &&
-      new Date().getTime() - state.playing.mouseStationarySince > 2000 &&
-      !state.playing.isPaused &&
-      state.playing.location === 'local' &&
-      state.playing.playbackRate === 1
-
-    var cls = [
-      'view-' + state.location.url(), /* e.g. view-home, view-player */
-      'is-' + process.platform /* e.g. is-darwin, is-win32, is-linux */
-    ]
-    if (state.window.isFullScreen) cls.push('is-fullscreen')
-    if (state.window.isFocused) cls.push('is-focused')
-    if (hideControls) cls.push('hide-video-controls')
-
-    var vdom = (
-      <MuiThemeProvider muiTheme={getMuiTheme(darkBaseTheme)}>
-        <div className={'app ' + cls.join(' ')}>
-          <Header state={state} />
-          {this.getErrorPopover()}
-          <div key='content' className='content'>{this.getView()}</div>
-          {this.getModal()}
-        </div>
-      </MuiThemeProvider>
-    )
-
-    return vdom
-  }
-
-  getErrorPopover () {
-    var state = this.props.state
-    var now = new Date().getTime()
-    var recentErrors = state.errors.filter((x) => now - x.time < 5000)
-    var hasErrors = recentErrors.length > 0
-
-    var errorElems = recentErrors.map(function (error, i) {
-      return (<div key={i} className='error'>{error.message}</div>)
-    })
-    return (
-      <div key='errors'
-        className={'error-popover ' + (hasErrors ? 'visible' : 'hidden')}>
-        <div key='title' className='title'>Error</div>
-        {errorElems}
-      </div>
-    )
-  }
-
-  getModal () {
-    var state = this.props.state
-    if (!state.modal) return
-    var ModalContents = Modals[state.modal.id]
-    return (
-      <div key='modal' className='modal'>
-        <div key='modal-background' className='modal-background' />
-        <div key='modal-content' className='modal-content'>
-          <ModalContents state={state} />
-        </div>
-      </div>
-    )
-  }
-
-  getView () {
-    var state = this.props.state
-    var View = Views[state.location.url()]
-    return (<View state={state} />)
-  }
-}
-
-module.exports = App
--- a/src/renderer/pages/CreateTorrentPage.js
+++ b/src/renderer/pages/CreateTorrentPage.js
@@ -1,171 +0,0 @@
-const createTorrent = require('create-torrent')
-const path = require('path')
-const prettyBytes = require('prettier-bytes')
-const React = require('react')
-
-const {dispatch, dispatcher} = require('../lib/dispatcher')
-
-const FlatButton = require('material-ui/FlatButton').default
-const RaisedButton = require('material-ui/RaisedButton').default
-const TextField = require('material-ui/TextField').default
-
-const CreateTorrentErrorPage = require('../components/create-torrent-error-page')
-const Heading = require('../components/Heading')
-const ShowMore = require('../components/ShowMore')
-
-class CreateTorrentPage extends React.Component {
-  constructor (props) {
-    super(props)
-
-    var state = this.props.state
-    var info = state.location.current()
-
-    // Preprocess: exclude .DS_Store and other dotfiles
-    var files = info.files
-      .filter((f) => !f.name.startsWith('.'))
-      .map((f) => ({name: f.name, path: f.path, size: f.size}))
-    if (files.length === 0) return (<CreateTorrentErrorPage state={state} />)
-
-    // First, extract the base folder that the files are all in
-    var pathPrefix = info.folderPath
-    if (!pathPrefix) {
-      pathPrefix = files.map((x) => x.path).reduce(findCommonPrefix)
-      if (!pathPrefix.endsWith('/') && !pathPrefix.endsWith('\\')) {
-        pathPrefix = path.dirname(pathPrefix)
-      }
-    }
-
-    // Sanity check: show the number of files and total size
-    var numFiles = files.length
-    var totalBytes = files
-      .map((f) => f.size)
-      .reduce((a, b) => a + b, 0)
-    var torrentInfo = `${numFiles} files, ${prettyBytes(totalBytes)}`
-
-    // Then, use the name of the base folder (or sole file, for a single file torrent)
-    // as the default name. Show all files relative to the base folder.
-    var defaultName, basePath
-    if (files.length === 1) {
-      // Single file torrent: /a/b/foo.jpg -> torrent name 'foo.jpg', path '/a/b'
-      defaultName = files[0].name
-      basePath = pathPrefix
-    } else {
-      // Multi file torrent: /a/b/{foo, bar}.jpg -> torrent name 'b', path '/a'
-      defaultName = path.basename(pathPrefix)
-      basePath = path.dirname(pathPrefix)
-    }
-    var maxFileElems = 100
-    var fileElems = files.slice(0, maxFileElems).map(function (file, i) {
-      var relativePath = files.length === 0 ? file.name : path.relative(pathPrefix, file.path)
-      return (<div key={i}>{relativePath}</div>)
-    })
-    if (files.length > maxFileElems) {
-      fileElems.push(<div key='more'>+ {maxFileElems - files.length} more</div>)
-    }
-    var trackers = createTorrent.announceList.join('\n')
-
-    this.state = {
-      basePath,
-      defaultName,
-      fileElems,
-      torrentInfo,
-      trackers
-    }
-  }
-
-  handleSubmit () {
-    var announceList = document.querySelector('.torrent-trackers').value
-      .split('\n')
-      .map((s) => s.trim())
-      .filter((s) => s !== '')
-    var isPrivate = document.querySelector('.torrent-is-private').checked
-    var comment = document.querySelector('.torrent-comment').value.trim()
-    var options = {
-      // We can't let the user choose their own name if we want WebTorrent
-      // to use the files in place rather than creating a new folder.
-      // If we ever want to add support for that:
-      // name: document.querySelector('.torrent-name').value
-      name: this.state.defaultName,
-      path: this.state.basePath,
-      files: this.state.files,
-      announce: announceList,
-      private: isPrivate,
-      comment: comment
-    }
-    dispatch('createTorrent', options)
-  }
-
-  render () {
-    return (
-      <div className='create-torrent'>
-        <Heading level={1}>
-          Create torrent "{this.state.defaultName}"
-        </Heading>
-        <div className='torrent-info'>
-          {this.state.torrentInfo}
-        </div>
-        <div className='torrent-attribute'>
-          <label>Path:</label>
-          <div className='torrent-attribute'>{this.state.pathPrefix}</div>
-        </div>
-        <ShowMore
-          style={{
-            marginBottom: 10
-          }}
-          hideLabel='Hide advanced settings...'
-          showLabel='Show advanced settings...'
-        >
-          <div key='advanced' className='create-torrent-advanced'>
-            <div key='private' className='torrent-attribute'>
-              <label>Private:</label>
-              <input type='checkbox' className='torrent-is-private' value='torrent-is-private' />
-            </div>
-            <Heading level={2}>Trackers:</Heading>
-            <TextField
-              className='torrent-trackers'
-              hintText='Tracker'
-              multiLine
-              rows={2}
-              rowsMax={10}
-              defaultValue={this.state.trackers}
-            />
-            <div key='comment' className='torrent-attribute'>
-              <label>Comment:</label>
-              <textarea className='torrent-attribute torrent-comment' />
-            </div>
-            <div key='files' className='torrent-attribute'>
-              <label>Files:</label>
-              <div>{this.state.fileElems}</div>
-            </div>
-          </div>
-        </ShowMore>
-        <div className='float-right'>
-          <FlatButton
-            label='Cancel'
-            style={{
-              marginRight: 10
-            }}
-            onClick={dispatcher('cancel')}
-          />
-          <RaisedButton
-            label='Create Torrent'
-            primary
-            onClick={this.handleSubmit}
-          />
-        </div>
-      </div>
-    )
-  }
-}
-
-// Finds the longest common prefix
-function findCommonPrefix (a, b) {
-  for (var i = 0; i < a.length && i < b.length; i++) {
-    if (a.charCodeAt(i) !== b.charCodeAt(i)) break
-  }
-  if (i === a.length) return a
-  if (i === b.length) return b
-  return a.substring(0, i)
-}
-
-module.exports = CreateTorrentPage
--- a/src/renderer/pages/app.js
+++ b/src/renderer/pages/app.js
@@ -0,0 +1,130 @@
+const colors = require('material-ui/styles/colors')
+const createGetter = require('fn-getter')
+const React = require('react')
+
+const darkBaseTheme = require('material-ui/styles/baseThemes/darkBaseTheme').default
+const getMuiTheme = require('material-ui/styles/getMuiTheme').default
+const MuiThemeProvider = require('material-ui/styles/MuiThemeProvider').default
+
+const Header = require('../components/header')
+
+// Perf optimization: Needed immediately, so do not lazy load it below
+const TorrentListPage = require('./torrent-list-page')
+
+const Views = {
+  'home': createGetter(() => TorrentListPage),
+  'player': createGetter(() => require('./player-page')),
+  'create-torrent': createGetter(() => require('./create-torrent-page')),
+  'preferences': createGetter(() => require('./preferences-page'))
+}
+
+const Modals = {
+  'open-torrent-address-modal': createGetter(
+    () => require('../components/open-torrent-address-modal')
+  ),
+  'remove-torrent-modal': createGetter(() => require('../components/remove-torrent-modal')),
+  'update-available-modal': createGetter(() => require('../components/update-available-modal')),
+  'unsupported-media-modal': createGetter(() => require('../components/unsupported-media-modal'))
+}
+
+const fontFamily = process.platform === 'win32'
+  ? '"Segoe UI", sans-serif'
+  : 'BlinkMacSystemFont, "Helvetica Neue", Helvetica, sans-serif'
+
+darkBaseTheme.fontFamily = fontFamily
+darkBaseTheme.userAgent = false
+darkBaseTheme.palette.primary1Color = colors.grey50
+darkBaseTheme.palette.primary2Color = colors.grey50
+darkBaseTheme.palette.primary3Color = colors.grey600
+darkBaseTheme.palette.accent1Color = colors.redA200
+darkBaseTheme.palette.accent2Color = colors.redA400
+darkBaseTheme.palette.accent3Color = colors.redA100
+
+let darkMuiTheme
+let lightMuiTheme
+
+class App extends React.Component {
+  render () {
+    const state = this.props.state
+
+    // Hide player controls while playing video, if the mouse stays still for a while
+    // Never hide the controls when:
+    // * The mouse is over the controls or we're scrubbing (see CSS)
+    // * The video is paused
+    // * The video is playing remotely on Chromecast or Airplay
+    const hideControls = state.shouldHidePlayerControls()
+
+    const cls = [
+      'view-' + state.location.url(), /* e.g. view-home, view-player */
+      'is-' + process.platform /* e.g. is-darwin, is-win32, is-linux */
+    ]
+    if (state.window.isFullScreen) cls.push('is-fullscreen')
+    if (state.window.isFocused) cls.push('is-focused')
+    if (hideControls) cls.push('hide-video-controls')
+
+    if (!darkMuiTheme) {
+      darkMuiTheme = getMuiTheme(darkBaseTheme)
+    }
+
+    return (
+      <MuiThemeProvider muiTheme={darkMuiTheme}>
+        <div className={'app ' + cls.join(' ')}>
+          <Header state={state} />
+          {this.getErrorPopover()}
+          <div key='content' className='content'>{this.getView()}</div>
+          {this.getModal()}
+        </div>
+      </MuiThemeProvider>
+    )
+  }
+
+  getErrorPopover () {
+    const state = this.props.state
+    const now = new Date().getTime()
+    const recentErrors = state.errors.filter((x) => now - x.time < 5000)
+    const hasErrors = recentErrors.length > 0
+
+    const errorElems = recentErrors.map(function (error, i) {
+      return (<div key={i} className='error'>{error.message}</div>)
+    })
+    return (
+      <div key='errors'
+        className={'error-popover ' + (hasErrors ? 'visible' : 'hidden')}>
+        <div key='title' className='title'>Error</div>
+        {errorElems}
+      </div>
+    )
+  }
+
+  getModal () {
+    const state = this.props.state
+    if (!state.modal) return
+
+    if (!lightMuiTheme) {
+      const lightBaseTheme = require('material-ui/styles/baseThemes/lightBaseTheme').default
+      lightBaseTheme.fontFamily = fontFamily
+      lightBaseTheme.userAgent = false
+      lightMuiTheme = getMuiTheme(lightBaseTheme)
+    }
+
+    const ModalContents = Modals[state.modal.id]()
+    return (
+      <MuiThemeProvider muiTheme={lightMuiTheme}>
+        <div key='modal' className='modal'>
+          <div key='modal-background' className='modal-background' />
+          <div key='modal-content' className='modal-content'>
+            <ModalContents state={state} />
+          </div>
+        </div>
+      </MuiThemeProvider>
+    )
+  }
+
+  getView () {
+    const state = this.props.state
+    const View = Views[state.location.url()]()
+    return (<View state={state} />)
+  }
+}
+
+module.exports = App
--- a/src/renderer/pages/create-torrent-page.js
+++ b/src/renderer/pages/create-torrent-page.js
@@ -0,0 +1,216 @@
+const createTorrent = require('create-torrent')
+const path = require('path')
+const prettyBytes = require('prettier-bytes')
+const React = require('react')
+
+const {dispatch, dispatcher} = require('../lib/dispatcher')
+
+const FlatButton = require('material-ui/FlatButton').default
+const RaisedButton = require('material-ui/RaisedButton').default
+const TextField = require('material-ui/TextField').default
+const Checkbox = require('material-ui/Checkbox').default
+
+const CreateTorrentErrorPage = require('../components/create-torrent-error-page')
+const Heading = require('../components/heading')
+const ShowMore = require('../components/show-more')
+
+// Shows a basic UI to create a torrent, from an already-selected file or folder.
+// Includes a "Show Advanced..." button and more advanced UI.
+class CreateTorrentPage extends React.Component {
+  constructor (props) {
+    super(props)
+
+    const state = this.props.state
+    const info = state.location.current()
+
+    // First, extract the base folder that the files are all in
+    let pathPrefix = info.folderPath
+    if (!pathPrefix) {
+      pathPrefix = info.files.map((x) => x.path).reduce(findCommonPrefix)
+      if (!pathPrefix.endsWith('/') && !pathPrefix.endsWith('\\')) {
+        pathPrefix = path.dirname(pathPrefix)
+      }
+    }
+
+    // Then, exclude .DS_Store and other dotfiles
+    const files = info.files
+      .filter((f) => !containsDots(f.path, pathPrefix))
+      .map((f) => ({name: f.name, path: f.path, size: f.size}))
+    if (files.length === 0) return (<CreateTorrentErrorPage state={state} />)
+
+    // Then, use the name of the base folder (or sole file, for a single file torrent)
+    // as the default name. Show all files relative to the base folder.
+    let defaultName, basePath
+    if (files.length === 1) {
+      // Single file torrent: /a/b/foo.jpg -> torrent name 'foo.jpg', path '/a/b'
+      defaultName = files[0].name
+      basePath = pathPrefix
+    } else {
+      // Multi file torrent: /a/b/{foo, bar}.jpg -> torrent name 'b', path '/a'
+      defaultName = path.basename(pathPrefix)
+      basePath = path.dirname(pathPrefix)
+    }
+
+    // Default trackers
+    const trackers = createTorrent.announceList.join('\n')
+
+    this.state = {
+      comment: '',
+      isPrivate: false,
+      pathPrefix,
+      basePath,
+      defaultName,
+      files,
+      trackers
+    }
+
+    // Create React event handlers only once
+    this.setIsPrivate = (_, isPrivate) => this.setState({isPrivate})
+    this.setComment = (_, comment) => this.setState({comment})
+    this.setTrackers = (_, trackers) => this.setState({trackers})
+    this.handleSubmit = handleSubmit.bind(this)
+  }
+
+  render () {
+    const files = this.state.files
+
+    // Sanity check: show the number of files and total size
+    const numFiles = files.length
+    const totalBytes = files
+      .map((f) => f.size)
+      .reduce((a, b) => a + b, 0)
+    const torrentInfo = `${numFiles} files, ${prettyBytes(totalBytes)}`
+
+    return (
+      <div className='create-torrent'>
+        <Heading level={1}>Create torrent {this.state.defaultName}</Heading>
+        <div className='torrent-info'>{torrentInfo}</div>
+        <div className='torrent-attribute'>
+          <label>Path:</label>
+          <div>{this.state.pathPrefix}</div>
+        </div>
+        <ShowMore
+          style={{
+            marginBottom: 10
+          }}
+          hideLabel='Hide advanced settings...'
+          showLabel='Show advanced settings...'>
+          {this.renderAdvanced()}
+        </ShowMore>
+        <div className='float-right'>
+          <FlatButton
+            className='control cancel'
+            label='Cancel'
+            style={{
+              marginRight: 10
+            }}
+            onClick={dispatcher('cancel')} />
+          <RaisedButton
+            className='control create-torrent-button'
+            label='Create Torrent'
+            primary
+            onClick={this.handleSubmit} />
+        </div>
+      </div>
+    )
+  }
+
+  // Renders everything after clicking Show Advanced...:
+  // * Is Private? (private torrents, not announced to DHT)
+  // * Announce list (trackers)
+  // * Comment
+  renderAdvanced () {
+    // Create file list
+    const maxFileElems = 100
+    const files = this.state.files
+    const fileElems = files.slice(0, maxFileElems).map((file, i) => {
+      const relativePath = path.relative(this.state.pathPrefix, file.path)
+      return (<div key={i}>{relativePath}</div>)
+    })
+    if (files.length > maxFileElems) {
+      fileElems.push(<div key='more'>+ {files.length - maxFileElems} more</div>)
+    }
+
+    // Align the text fields
+    const textFieldStyle = { width: '' }
+    const textareaStyle = { margin: 0 }
+
+    return (
+      <div key='advanced' className='create-torrent-advanced'>
+        <div key='private' className='torrent-attribute'>
+          <label>Private:</label>
+          <Checkbox
+            className='torrent-is-private control'
+            style={{display: ''}}
+            checked={this.state.isPrivate}
+            onCheck={this.setIsPrivate} />
+        </div>
+        <div key='trackers' className='torrent-attribute'>
+          <label>Trackers:</label>
+          <TextField
+            className='torrent-trackers control'
+            style={textFieldStyle}
+            textareaStyle={textareaStyle}
+            multiLine
+            rows={2}
+            rowsMax={10}
+            value={this.state.trackers}
+            onChange={this.setTrackers} />
+        </div>
+        <div key='comment' className='torrent-attribute'>
+          <label>Comment:</label>
+          <TextField
+            className='torrent-comment control'
+            style={textFieldStyle}
+            textareaStyle={textareaStyle}
+            hintText='Optionally describe your torrent...'
+            multiLine
+            rows={2}
+            rowsMax={10}
+            value={this.state.comment}
+            onChange={this.setComment} />
+        </div>
+        <div key='files' className='torrent-attribute'>
+          <label>Files:</label>
+          <div>{fileElems}</div>
+        </div>
+      </div>
+    )
+  }
+}
+
+function handleSubmit () {
+  const announceList = this.state.trackers
+    .split('\n')
+    .map((s) => s.trim())
+    .filter((s) => s !== '')
+  const options = {
+    // We can't let the user choose their own name if we want WebTorrent
+    // to use the files in place rather than creating a new folder.
+    name: this.state.defaultName,
+    path: this.state.basePath,
+    files: this.state.files,
+    announce: announceList,
+    private: this.state.isPrivate,
+    comment: this.state.comment.trim()
+  }
+  dispatch('createTorrent', options)
+}
+
+// Finds the longest common prefix
+function findCommonPrefix (a, b) {
+  let i
+  for (i = 0; i < a.length && i < b.length; i++) {
+    if (a.charCodeAt(i) !== b.charCodeAt(i)) break
+  }
+  if (i === a.length) return a
+  if (i === b.length) return b
+  return a.substring(0, i)
+}
+
+function containsDots (path, pathPrefix) {
+  const suffix = path.substring(pathPrefix.length).replace(/\\/g, '/')
+  return ('/' + suffix).includes('/.')
+}
+
+module.exports = CreateTorrentPage
--- a/src/renderer/pages/player-page.js
+++ b/src/renderer/pages/player-page.js
@@ -2,19 +2,20 @@ const React = require('react')
 const Bitfield = require('bitfield')
 const prettyBytes = require('prettier-bytes')
 const zeroFill = require('zero-fill')
-const path = require('path')

 const TorrentSummary = require('../lib/torrent-summary')
+const Playlist = require('../lib/playlist')
 const {dispatch, dispatcher} = require('../lib/dispatcher')
+const config = require('../../config')

 // Shows a streaming video player. Standard features + Chromecast + Airplay
 module.exports = class Player extends React.Component {
  render () {
    // Show the video as large as will fit in the window, play immediately
    // If the video is on Chromecast or Airplay, show a title screen instead
-    var state = this.props.state
-    var showVideo = state.playing.location === 'local'
-    var showControls = state.playing.location !== 'external'
+    const state = this.props.state
+    const showVideo = state.playing.location === 'local'
+    const showControls = state.playing.location !== 'external'
    return (
      <div
        className='player'
@@ -25,6 +26,15 @@ module.exports = class Player extends React.Component {
      </div>
    )
  }
+
+  onComponentWillUnmount () {
+    // Unload the media element so that Chromium stops trying to fetch data
+    const tag = document.querySelector('audio,video')
+    if (!tag) return
+    tag.pause()
+    tag.src = ''
+    tag.load()
+  }
 }

 // Handles volume change by wheel
@@ -38,7 +48,7 @@ function renderMedia (state) {
  // Unfortunately, play/pause can't be done just by modifying HTML.
  // Instead, grab the DOM node and play/pause it if necessary
  // Get the <video> or <audio> tag
-  var mediaElement = document.querySelector(state.playing.type)
+  const mediaElement = document.querySelector(state.playing.type)
  if (mediaElement !== null) {
    if (state.playing.isPaused && !mediaElement.paused) {
      mediaElement.pause()
@@ -66,20 +76,20 @@ function renderMedia (state) {
    }

    // Switch to the newly added subtitle track, if available
-    var tracks = mediaElement.textTracks || []
-    for (var j = 0; j < tracks.length; j++) {
-      var isSelectedTrack = j === state.playing.subtitles.selectedIndex
+    const tracks = mediaElement.textTracks || []
+    for (let j = 0; j < tracks.length; j++) {
+      const isSelectedTrack = j === state.playing.subtitles.selectedIndex
      tracks[j].mode = isSelectedTrack ? 'showing' : 'hidden'
    }

    // Save video position
-    var file = state.getPlayingFileSummary()
+    const file = state.getPlayingFileSummary()
    file.currentTime = state.playing.currentTime = mediaElement.currentTime
    file.duration = state.playing.duration = mediaElement.duration

    // Save selected subtitle
    if (state.playing.subtitles.selectedIndex !== -1) {
-      var index = state.playing.subtitles.selectedIndex
+      const index = state.playing.subtitles.selectedIndex
      file.selectedSubtitle = state.playing.subtitles.tracks[index].filePath
    } else if (file.selectedSubtitle != null) {
      delete file.selectedSubtitle
@@ -89,11 +99,11 @@ function renderMedia (state) {
  }

  // Add subtitles to the <video> tag
-  var trackTags = []
+  const trackTags = []
  if (state.playing.subtitles.selectedIndex >= 0) {
-    for (var i = 0; i < state.playing.subtitles.tracks.length; i++) {
-      var track = state.playing.subtitles.tracks[i]
-      var isSelected = state.playing.subtitles.selectedIndex === i
+    for (let i = 0; i < state.playing.subtitles.tracks.length; i++) {
+      const track = state.playing.subtitles.tracks[i]
+      const isSelected = state.playing.subtitles.selectedIndex === i
      trackTags.push(
        <track
          key={i}
@@ -106,10 +116,10 @@ function renderMedia (state) {
  }

  // Create the <audio> or <video> tag
-  var MediaTagName = state.playing.type
-  var mediaTag = (
+  const MediaTagName = state.playing.type
+  const mediaTag = (
    <MediaTagName
-      src={state.server.localURL}
+      src={Playlist.getCurrentLocalURL(state)}
      onDoubleClick={dispatcher('toggleFullScreen')}
      onLoadedMetadata={onLoadedMetadata}
      onEnded={onEnded}
@@ -136,21 +146,25 @@ function renderMedia (state) {
  // As soon as we know the video dimensions, resize the window
  function onLoadedMetadata (e) {
    if (state.playing.type !== 'video') return
-    var video = e.target
-    var dimensions = {
+    const video = e.target
+    const dimensions = {
      width: video.videoWidth,
      height: video.videoHeight
    }
    dispatch('setDimensions', dimensions)
  }

-  // When the video completes, pause the video instead of looping
  function onEnded (e) {
-    state.playing.isPaused = true
+    if (Playlist.hasNext(state)) {
+      dispatch('nextTrack')
+    } else {
+      // When the last video completes, pause the video instead of looping
+      state.playing.isPaused = true
+    }
  }

  function onCanPlay (e) {
-    var elem = e.target
+    const elem = e.target
    if (state.playing.type === 'video' &&
      elem.webkitVideoDecodedByteCount === 0) {
      dispatch('mediaError', 'Video codec unsupported')
@@ -164,15 +178,15 @@ function renderMedia (state) {
 }

 function renderOverlay (state) {
-  var elems = []
-  var audioMetadataElem = renderAudioMetadata(state)
-  var spinnerElem = renderLoadingSpinner(state)
+  const elems = []
+  const audioMetadataElem = renderAudioMetadata(state)
+  const spinnerElem = renderLoadingSpinner(state)
  if (audioMetadataElem) elems.push(audioMetadataElem)
  if (spinnerElem) elems.push(spinnerElem)

  // Video fills the window, centered with black bars if necessary
  // Audio gets a static poster image and a summary of the file metadata.
-  var style
+  let style
  if (state.playing.type === 'audio') {
    style = { backgroundImage: cssBackgroundImagePoster(state) }
  } else if (elems.length !== 0) {
@@ -190,27 +204,27 @@ function renderOverlay (state) {
 }

 function renderAudioMetadata (state) {
-  var fileSummary = state.getPlayingFileSummary()
+  const fileSummary = state.getPlayingFileSummary()
  if (!fileSummary.audioInfo) return
-  var info = fileSummary.audioInfo
+  const info = fileSummary.audioInfo

  // Get audio track info
-  var title = info.title
+  let title = info.title
  if (!title) {
    title = fileSummary.name
  }
-  var artist = info.artist && info.artist[0]
-  var album = info.album
+  let artist = info.artist && info.artist[0]
+  let album = info.album
  if (album && info.year && !album.includes(info.year)) {
    album += ' (' + info.year + ')'
  }
-  var track
+  let track
  if (info.track && info.track.no && info.track.of) {
    track = info.track.no + ' of ' + info.track.of
  }

  // Show a small info box in the middle of the screen with title/album/etc
-  var elems = []
+  const elems = []
  if (artist) {
    elems.push((
      <div key='artist' className='audio-artist'>
@@ -234,7 +248,7 @@ function renderAudioMetadata (state) {
  }

  // Align the title with the other info, if available. Otherwise, center title
-  var emptyLabel = (<label />)
+  const emptyLabel = (<label />)
  elems.unshift((
    <div key='title' className='audio-title'>
      {elems.length ? emptyLabel : undefined}{title}
@@ -246,14 +260,14 @@ function renderAudioMetadata (state) {

 function renderLoadingSpinner (state) {
  if (state.playing.isPaused) return
-  var isProbablyStalled = state.playing.isStalled ||
+  const isProbablyStalled = state.playing.isStalled ||
    (new Date().getTime() - state.playing.lastTimeUpdate > 2000)
  if (!isProbablyStalled) return

-  var prog = state.getPlayingTorrentSummary().progress || {}
-  var fileProgress = 0
+  const prog = state.getPlayingTorrentSummary().progress || {}
+  let fileProgress = 0
  if (prog.files) {
-    var file = prog.files[state.playing.fileIndex]
+    const file = prog.files[state.playing.fileIndex]
    fileProgress = Math.floor(100 * file.numPiecesPresent / file.numPieces)
  }

@@ -261,16 +275,16 @@ function renderLoadingSpinner (state) {
    <div key='loading' className='media-stalled'>
      <div key='loading-spinner' className='loading-spinner'>&nbsp;</div>
      <div key='loading-progress' className='loading-status ellipsis'>
-        <span className='progress'>{fileProgress}%</span> downloaded,
-        <span>↓ {prettyBytes(prog.downloadSpeed || 0)}/s</span>
-        <span>↑ {prettyBytes(prog.uploadSpeed || 0)}/s</span>
+        <span className='progress'>{fileProgress}%</span> downloaded
+        <span> ↓ {prettyBytes(prog.downloadSpeed || 0)}/s</span>
+        <span> ↑ {prettyBytes(prog.uploadSpeed || 0)}/s</span>
      </div>
    </div>
  )
 }

 function renderCastScreen (state) {
-  var castIcon, castType, isCast
+  let castIcon, castType, isCast
  if (state.playing.location.startsWith('chromecast')) {
    castIcon = 'cast_connected'
    castType = 'Chromecast'
@@ -284,11 +298,8 @@ function renderCastScreen (state) {
    castType = 'DLNA'
    isCast = true
  } else if (state.playing.location === 'external') {
-    // TODO: get the player name in a more reliable way
-    var playerPath = state.saved.prefs.externalPlayerPath
-    var playerName = playerPath ? path.basename(playerPath).split('.')[0] : 'VLC'
    castIcon = 'tv'
-    castType = playerName
+    castType = state.getExternalPlayerName()
    isCast = false
  } else if (state.playing.location === 'error') {
    castIcon = 'error_outline'
@@ -296,15 +307,15 @@ function renderCastScreen (state) {
    isCast = false
  }

-  var isStarting = state.playing.location.endsWith('-pending')
-  var castName = state.playing.castName
-  var castStatus
+  const isStarting = state.playing.location.endsWith('-pending')
+  const castName = state.playing.castName
+  let castStatus
  if (isCast && isStarting) castStatus = 'Connecting to ' + castName + '...'
  else if (isCast && !isStarting) castStatus = 'Connected to ' + castName
  else castStatus = ''

  // Show a nice title image, if possible
-  var style = {
+  const style = {
    backgroundImage: cssBackgroundImagePoster(state)
  }

@@ -322,12 +333,12 @@ function renderCastScreen (state) {
 function renderCastOptions (state) {
  if (!state.devices.castMenu) return

-  var {location, devices} = state.devices.castMenu
-  var player = state.devices[location]
+  const {location, devices} = state.devices.castMenu
+  const player = state.devices[location]

-  var items = devices.map(function (device, ix) {
-    var isSelected = player.device === device
-    var name = device.name
+  const items = devices.map(function (device, ix) {
+    const isSelected = player.device === device
+    const name = device.name
    return (
      <li key={ix} onClick={dispatcher('selectCastDevice', ix)}>
        <i className='icon'>{isSelected ? 'radio_button_checked' : 'radio_button_unchecked'}</i>
@@ -344,11 +355,11 @@ function renderCastOptions (state) {
 }

 function renderSubtitleOptions (state) {
-  var subtitles = state.playing.subtitles
+  const subtitles = state.playing.subtitles
  if (!subtitles.tracks.length || !subtitles.showMenu) return

-  var items = subtitles.tracks.map(function (track, ix) {
-    var isSelected = state.playing.subtitles.selectedIndex === ix
+  const items = subtitles.tracks.map(function (track, ix) {
+    const isSelected = state.playing.subtitles.selectedIndex === ix
    return (
      <li key={ix} onClick={dispatcher('selectSubtitle', ix)}>
        <i className='icon'>{'radio_button_' + (isSelected ? 'checked' : 'unchecked')}</i>
@@ -357,8 +368,8 @@ function renderSubtitleOptions (state) {
    )
  })

-  var noneSelected = state.playing.subtitles.selectedIndex === -1
-  var noneClass = 'radio_button_' + (noneSelected ? 'checked' : 'unchecked')
+  const noneSelected = state.playing.subtitles.selectedIndex === -1
+  const noneClass = 'radio_button_' + (noneSelected ? 'checked' : 'unchecked')
  return (
    <ul key='subtitle-options' className='options-list'>
      {items}
@@ -371,32 +382,39 @@ function renderSubtitleOptions (state) {
 }

 function renderPlayerControls (state) {
-  var positionPercent = 100 * state.playing.currentTime / state.playing.duration
-  var playbackCursorStyle = { left: 'calc(' + positionPercent + '% - 3px)' }
-  var captionsClass = state.playing.subtitles.tracks.length === 0
+  const positionPercent = 100 * state.playing.currentTime / state.playing.duration
+  const playbackCursorStyle = { left: 'calc(' + positionPercent + '% - 3px)' }
+  const captionsClass = state.playing.subtitles.tracks.length === 0
    ? 'disabled'
    : state.playing.subtitles.selectedIndex >= 0
      ? 'active'
      : ''
+  const prevClass = Playlist.hasPrevious(state) ? '' : 'disabled'
+  const nextClass = Playlist.hasNext(state) ? '' : 'disabled'

-  var elements = [
+  const elements = [
    <div key='playback-bar' className='playback-bar'>
      {renderLoadingBar(state)}
      <div
        key='cursor'
        className='playback-cursor'
-        style={playbackCursorStyle}
-      />
+        style={playbackCursorStyle} />
      <div
        key='scrub-bar'
        className='scrub-bar'
        draggable='true'
        onDragStart={handleDragStart}
        onClick={handleScrub}
-        onDrag={handleScrub}
-      />
+        onDrag={handleScrub} />
    </div>,

+    <i
+      key='skip-previous'
+      className={'icon skip-previous float-left ' + prevClass}
+      onClick={dispatcher('previousTrack')}>
+      skip_previous
+    </i>,
+
    <i
      key='play'
      className='icon play-pause float-left'
@@ -404,6 +422,13 @@ function renderPlayerControls (state) {
      {state.playing.isPaused ? 'play_arrow' : 'pause'}
    </i>,

+    <i
+      key='skip-next'
+      className={'icon skip-next float-left ' + nextClass}
+      onClick={dispatcher('nextTrack')}>
+      skip_next
+    </i>,
+
    <i
      key='fullscreen'
      className='icon fullscreen float-right'
@@ -413,7 +438,7 @@ function renderPlayerControls (state) {
  ]

  if (state.playing.type === 'video') {
-    // show closed captions icon
+    // Show closed captions icon
    elements.push((
      <i
        key='subtitles'
@@ -425,24 +450,24 @@ function renderPlayerControls (state) {
  }

  // If we've detected a Chromecast or AppleTV, the user can play video there
-  var castTypes = ['chromecast', 'airplay', 'dlna']
-  var isCastingAnywhere = castTypes.some(
+  const castTypes = ['chromecast', 'airplay', 'dlna']
+  const isCastingAnywhere = castTypes.some(
    (castType) => state.playing.location.startsWith(castType))

  // Add the cast buttons. Icons for each cast type, connected/disconnected:
-  var buttonIcons = {
+  const buttonIcons = {
    'chromecast': {true: 'cast_connected', false: 'cast'},
    'airplay': {true: 'airplay', false: 'airplay'},
    'dlna': {true: 'tv', false: 'tv'}
  }
  castTypes.forEach(function (castType) {
    // Do we show this button (eg. the Chromecast button) at all?
-    var isCasting = state.playing.location.startsWith(castType)
-    var player = state.devices[castType]
+    const isCasting = state.playing.location.startsWith(castType)
+    const player = state.devices[castType]
    if ((!player || player.getDevices().length === 0) && !isCasting) return

    // Show the button. Three options for eg the Chromecast button:
-    var buttonClass, buttonHandler
+    let buttonClass, buttonHandler
    if (isCasting) {
      // Option 1: we are currently connected to Chromecast. Button stops the cast.
      buttonClass = 'active'
@@ -456,7 +481,7 @@ function renderPlayerControls (state) {
      buttonClass = ''
      buttonHandler = dispatcher('toggleCastMenu', castType)
    }
-    var buttonIcon = buttonIcons[castType][isCasting]
+    const buttonIcon = buttonIcons[castType][isCasting]

    elements.push((
      <i
@@ -469,20 +494,18 @@ function renderPlayerControls (state) {
  })

  // Render volume slider
-  var volume = state.playing.volume
-  var volumeIcon = 'volume_' + (
+  const volume = state.playing.volume
+  const volumeIcon = 'volume_' + (
    volume === 0 ? 'off'
    : volume < 0.3 ? 'mute'
    : volume < 0.6 ? 'down'
    : 'up')
-  var volumeStyle = {
+  const volumeStyle = {
    background: '-webkit-gradient(linear, left top, right top, ' +
      'color-stop(' + (volume * 100) + '%, #eee), ' +
      'color-stop(' + (volume * 100) + '%, #727272))'
  }

-  // TODO: dcposch change the range input to use value / onChanged instead of
-  // "readonly" / onMouse[Down,Move,Up]
  elements.push((
    <div key='volume' className='volume float-left'>
      <i
@@ -495,21 +518,20 @@ function renderPlayerControls (state) {
        type='range' min='0' max='1' step='0.05'
        value={volume}
        onChange={handleVolumeScrub}
-        style={volumeStyle}
-      />
+        style={volumeStyle} />
    </div>
  ))

  // Show video playback progress
-  var currentTimeStr = formatTime(state.playing.currentTime)
-  var durationStr = formatTime(state.playing.duration)
+  const currentTimeStr = formatTime(state.playing.currentTime)
+  const durationStr = formatTime(state.playing.duration)
  elements.push((
    <span key='time' className='time float-left'>
      {currentTimeStr} / {durationStr}
    </span>
  ))

-  // render playback rate
+  // Render playback rate
  if (state.playing.playbackRate !== 1) {
    elements.push((
      <span key='rate' className='rate float-left'>
@@ -519,7 +541,9 @@ function renderPlayerControls (state) {
  }

  return (
-    <div key='controls' className='controls'>
+    <div key='controls' className='controls'
+      onMouseEnter={dispatcher('mediaControlsMouseEnter')}
+      onMouseLeave={dispatcher('mediaControlsMouseLeave')}>
      {elements}
      {renderCastOptions(state)}
      {renderSubtitleOptions(state)}
@@ -529,7 +553,7 @@ function renderPlayerControls (state) {
  function handleDragStart (e) {
    // Prevent the cursor from changing, eg to a green + icon on Mac
    if (e.dataTransfer) {
-      var dt = e.dataTransfer
+      const dt = e.dataTransfer
      dt.effectAllowed = 'none'
    }
  }
@@ -538,9 +562,9 @@ function renderPlayerControls (state) {
  function handleScrub (e) {
    if (!e.clientX) return
    dispatch('mediaMouseMoved')
-    var windowWidth = document.querySelector('body').clientWidth
-    var fraction = e.clientX / windowWidth
-    var position = fraction * state.playing.duration /* seconds */
+    const windowWidth = document.querySelector('body').clientWidth
+    const fraction = e.clientX / windowWidth
+    const position = fraction * state.playing.duration /* seconds */
    dispatch('skipTo', position)
  }

@@ -571,18 +595,23 @@ function renderPlayerControls (state) {
 // Renders the loading bar. Shows which parts of the torrent are loaded, which
 // can be 'spongey' / non-contiguous
 function renderLoadingBar (state) {
-  var torrentSummary = state.getPlayingTorrentSummary()
+  if (config.IS_TEST) return // Don't integration test the loading bar. Screenshots won't match.
+
+  const torrentSummary = state.getPlayingTorrentSummary()
  if (!torrentSummary.progress) {
-    return []
+    return null
  }

  // Find all contiguous parts of the torrent which are loaded
-  var prog = torrentSummary.progress
-  var fileProg = prog.files[state.playing.fileIndex]
-  var parts = []
-  var lastPiecePresent = false
-  for (var i = fileProg.startPiece; i <= fileProg.endPiece; i++) {
-    var partPresent = Bitfield.prototype.get.call(prog.bitfield, i)
+  const prog = torrentSummary.progress
+  const fileProg = prog.files[state.playing.fileIndex]
+
+  if (!fileProg) return null
+
+  const parts = []
+  let lastPiecePresent = false
+  for (let i = fileProg.startPiece; i <= fileProg.endPiece; i++) {
+    const partPresent = Bitfield.prototype.get.call(prog.bitfield, i)
    if (partPresent && !lastPiecePresent) {
      parts.push({start: i - fileProg.startPiece, count: 1})
    } else if (partPresent) {
@@ -592,21 +621,22 @@ function renderLoadingBar (state) {
  }

  // Output some bars to show which parts of the file are loaded
-  var loadingBarElems = parts.map(function (part, i) {
-    var style = {
+  const loadingBarElems = parts.map(function (part, i) {
+    const style = {
      left: (100 * part.start / fileProg.numPieces) + '%',
      width: (100 * part.count / fileProg.numPieces) + '%'
    }

    return (<div key={i} className='loading-bar-part' style={style} />)
  })
+
  return (<div key='loading-bar' className='loading-bar'>{loadingBarElems}</div>)
 }

 // Returns the CSS background-image string for a poster image + dark vignette
 function cssBackgroundImagePoster (state) {
-  var torrentSummary = state.getPlayingTorrentSummary()
-  var posterPath = TorrentSummary.getPosterPath(torrentSummary)
+  const torrentSummary = state.getPlayingTorrentSummary()
+  const posterPath = TorrentSummary.getPosterPath(torrentSummary)
  if (!posterPath) return ''
  return cssBackgroundImageDarkGradient() + `, url('${posterPath}')`
 }
@@ -621,12 +651,12 @@ function formatTime (time) {
    return '0:00'
  }

-  var hours = Math.floor(time / 3600)
-  var minutes = Math.floor(time % 3600 / 60)
+  let hours = Math.floor(time / 3600)
+  let minutes = Math.floor(time % 3600 / 60)
  if (hours > 0) {
    minutes = zeroFill(2, minutes)
  }
-  var seconds = zeroFill(2, Math.floor(time % 60))
+  let seconds = zeroFill(2, Math.floor(time % 60))

  return (hours > 0 ? hours + ':' : '') + minutes + ':' + seconds
 }
--- a/src/renderer/pages/preferences-page.js
+++ b/src/renderer/pages/preferences-page.js
@@ -1,13 +1,14 @@
-const colors = require('material-ui/styles/colors')
 const path = require('path')
 const React = require('react')

+const colors = require('material-ui/styles/colors')
 const Checkbox = require('material-ui/Checkbox').default
-const Heading = require('../components/Heading')
-const PathSelector = require('../components/PathSelector')
 const RaisedButton = require('material-ui/RaisedButton').default
+const Heading = require('../components/heading')
+const PathSelector = require('../components/path-selector')

 const {dispatch} = require('../lib/dispatcher')
+const config = require('../../config')

 class PreferencesPage extends React.Component {
  constructor (props) {
@@ -21,6 +22,9 @@ class PreferencesPage extends React.Component {

    this.handleExternalPlayerPathChange =
      this.handleExternalPlayerPathChange.bind(this)
+
+    this.handleStartupChange =
+      this.handleStartupChange.bind(this)
  }

  downloadPathSelector () {
@@ -33,8 +37,7 @@ class PreferencesPage extends React.Component {
          }}
          onChange={this.handleDownloadPathChange}
          title='Download location'
-          value={this.props.state.unsaved.prefs.downloadPath}
-        />
+          value={this.props.state.unsaved.prefs.downloadPath} />
      </Preference>
    )
  }
@@ -50,8 +53,7 @@ class PreferencesPage extends React.Component {
          className='control'
          checked={!this.props.state.unsaved.prefs.openExternalPlayer}
          label={'Play torrent media files using WebTorrent'}
-          onCheck={this.handleOpenExternalPlayerChange}
-        />
+          onCheck={this.handleOpenExternalPlayerChange} />
      </Preference>
    )
  }
@@ -67,7 +69,7 @@ class PreferencesPage extends React.Component {
          className='control'
          checked={this.props.state.unsaved.prefs.highestPlaybackPriority}
          label={'Highest Playback Priority'}
-          onCheck={this.handleHighestPlaybackPriorityChange}
+          onCheck={this.handleHighestPlaybackPriorityChange} 
        />
        <p>Pauses all active torrents to allow playback to use all of the available bandwidth.</p>
      </Preference>
@@ -79,14 +81,12 @@ class PreferencesPage extends React.Component {
  }

  externalPlayerPathSelector () {
-    const playerName = path.basename(
-      this.props.state.unsaved.prefs.externalPlayerPath || 'VLC'
-    )
+    const playerPath = this.props.state.unsaved.prefs.externalPlayerPath
+    const playerName = this.props.state.getExternalPlayerName()

    const description = this.props.state.unsaved.prefs.openExternalPlayer
      ? `Torrent media files will always play in ${playerName}.`
-      : `Torrent media files will play in ${playerName} if WebTorrent cannot ` +
-        'play them.'
+      : `Torrent media files will play in ${playerName} if WebTorrent cannot play them.`

    return (
      <Preference>
@@ -99,48 +99,70 @@ class PreferencesPage extends React.Component {
          displayValue={playerName}
          onChange={this.handleExternalPlayerPathChange}
          title='External player'
-          value={this.props.state.unsaved.prefs.externalPlayerPath}
-        />
+          value={playerPath ? path.dirname(playerPath) : null} />
      </Preference>
    )
  }

  handleExternalPlayerPathChange (filePath) {
-    if (path.extname(filePath) === '.app') {
-      // Mac: Use executable in packaged .app bundle
-      filePath += '/Contents/MacOS/' + path.basename(filePath, '.app')
-    }
    dispatch('updatePreferences', 'externalPlayerPath', filePath)
  }

  setDefaultAppButton () {
+    const isFileHandler = this.props.state.unsaved.prefs.isFileHandler
+    if (isFileHandler) {
+      return (
+        <Preference>
+          <p>WebTorrent is your default torrent app. Hooray!</p>
+        </Preference>
+      )
+    }
    return (
      <Preference>
        <p>WebTorrent is not currently the default torrent app.</p>
        <RaisedButton
          className='control'
          onClick={this.handleSetDefaultApp}
-          label='Make WebTorrent the default'
-        />
+          label='Make WebTorrent the default' />
      </Preference>
    )
  }

+  handleStartupChange (e, isChecked) {
+    dispatch('updatePreferences', 'startup', isChecked)
+  }
+
+  setStartupSection () {
+    if (config.IS_PORTABLE) {
+      return
+    }
+
+    return (
+      <PreferencesSection title='Startup'>
+        <Preference>
+          <Checkbox
+            className='control'
+            checked={this.props.state.unsaved.prefs.startup}
+            label={'Open WebTorrent on startup.'}
+            onCheck={this.handleStartupChange}
+          />
+        </Preference>
+      </PreferencesSection>
+    )
+  }
+
  handleSetDefaultApp () {
-    window.alert('TODO')
-    // var isFileHandler = state.unsaved.prefs.isFileHandler
-    // dispatch('updatePreferences', 'isFileHandler', !isFileHandler)
+    dispatch('updatePreferences', 'isFileHandler', true)
  }

  render () {
+    const style = {
+      color: colors.grey400,
+      marginLeft: 25,
+      marginRight: 25
+    }
    return (
-      <div
-        style={{
-          color: colors.grey400,
-          marginLeft: 25,
-          marginRight: 25
-        }}
-      >
+      <div style={style}>
        <PreferencesSection title='Downloads'>
          {this.downloadPathSelector()}
        </PreferencesSection>
@@ -152,6 +174,7 @@ class PreferencesPage extends React.Component {
        <PreferencesSection title='Default torrent app'>
          {this.setDefaultAppButton()}
        </PreferencesSection>
+        {this.setStartupSection()}
      </div>
    )
  }
@@ -165,13 +188,12 @@ class PreferencesSection extends React.Component {
  }

  render () {
+    const style = {
+      marginBottom: 25,
+      marginTop: 25
+    }
    return (
-      <div
-        style={{
-          marginBottom: 25,
-          marginTop: 25
-        }}
-      >
+      <div style={style}>
        <Heading level={2}>{this.props.title}</Heading>
        {this.props.children}
      </div>
@@ -181,15 +203,8 @@ class PreferencesSection extends React.Component {

 class Preference extends React.Component {
  render () {
-    return (
-      <div
-        style={{
-          marginBottom: 10
-        }}
-      >
-        {this.props.children}
-      </div>
-    )
+    const style = { marginBottom: 10 }
+    return (<div style={style}>{this.props.children}</div>)
  }
 }

--- a/src/renderer/pages/torrent-list-page.js
+++ b/src/renderer/pages/torrent-list-page.js
@@ -1,15 +1,18 @@
 const React = require('react')
 const prettyBytes = require('prettier-bytes')

+const Checkbox = require('material-ui/Checkbox').default
+const LinearProgress = require('material-ui/LinearProgress').default
+
 const TorrentSummary = require('../lib/torrent-summary')
 const TorrentPlayer = require('../lib/torrent-player')
 const {dispatcher} = require('../lib/dispatcher')

 module.exports = class TorrentList extends React.Component {
  render () {
-    var state = this.props.state
+    const state = this.props.state

-    var contents = []
+    const contents = []
    if (state.downloadPathStatus === 'missing') {
      contents.push(
        <div key='torrent-missing-path'>
@@ -21,7 +24,7 @@ module.exports = class TorrentList extends React.Component {
        </div>
      )
    }
-    var torrentElems = state.saved.torrents.map(
+    const torrentElems = state.saved.torrents.map(
      (torrentSummary) => this.renderTorrent(torrentSummary)
    )
    contents.push(...torrentElems)
@@ -39,30 +42,27 @@ module.exports = class TorrentList extends React.Component {
  }

  renderTorrent (torrentSummary) {
-    var state = this.props.state
-    var infoHash = torrentSummary.infoHash
-    var isSelected = infoHash && state.selectedInfoHash === infoHash
+    const state = this.props.state
+    const infoHash = torrentSummary.infoHash
+    const isSelected = infoHash && state.selectedInfoHash === infoHash

    // Background image: show some nice visuals, like a frame from the movie, if possible
-    var style = {}
+    const style = {}
    if (torrentSummary.posterFileName) {
-      var gradient = isSelected
-        ? 'linear-gradient(to bottom, rgba(0, 0, 0, 0.8) 0%, rgba(0, 0, 0, 0.4) 100%)'
-        : 'linear-gradient(to bottom, rgba(0, 0, 0, 0.5) 0%, rgba(0, 0, 0, 0) 100%)'
-      var posterPath = TorrentSummary.getPosterPath(torrentSummary)
-      style.backgroundImage = gradient + `, url('${posterPath}')`
+      const gradient = 'linear-gradient(to bottom, rgba(0, 0, 0, 0.4) 0%, rgba(0, 0, 0, 0.4) 100%)'
+      const posterPath = TorrentSummary.getPosterPath(torrentSummary)
+      style.backgroundImage = `${gradient}, url('${posterPath}')`
    }

    // Foreground: name of the torrent, basic info like size, play button,
    // cast buttons if available, and delete
-    var classes = ['torrent']
-    //  playStatus turns the play button into a loading spinner or error icon
-    if (torrentSummary.playStatus) classes.push(torrentSummary.playStatus)
+    const classes = ['torrent']
    if (isSelected) classes.push('selected')
    if (!infoHash) classes.push('disabled')
    if (!torrentSummary.torrentKey) throw new Error('Missing torrentKey')
    return (
      <div
+        id={torrentSummary.testID && ('torrent-' + torrentSummary.testID)}
        key={torrentSummary.torrentKey}
        style={style}
        className={classes.join(' ')}
@@ -71,48 +71,96 @@ module.exports = class TorrentList extends React.Component {
        {this.renderTorrentMetadata(torrentSummary)}
        {infoHash ? this.renderTorrentButtons(torrentSummary) : null}
        {isSelected ? this.renderTorrentDetails(torrentSummary) : null}
+        <hr />
      </div>
    )
  }

  // Show name, download status, % complete
  renderTorrentMetadata (torrentSummary) {
-    var name = torrentSummary.name || 'Loading torrent...'
-    var elements = [(
+    const name = torrentSummary.name || 'Loading torrent...'
+    const elements = [(
      <div key='name' className='name ellipsis'>{name}</div>
    )]

    // If it's downloading/seeding then show progress info
-    var prog = torrentSummary.progress
+    const prog = torrentSummary.progress
+    let progElems
    if (torrentSummary.error) {
-      elements.push(
-        <div key='progress-info' className='ellipsis'>
-          {getErrorMessage(torrentSummary)}
-        </div>
-      )
+      progElems = [getErrorMessage(torrentSummary)]
    } else if (torrentSummary.status !== 'paused' && prog) {
-      elements.push(
-        <div key='progress-info' className='ellipsis'>
-          {renderPercentProgress()}
-          {renderTotalProgress()}
-          {renderPeers()}
-          {renderDownloadSpeed()}
-          {renderUploadSpeed()}
-          {renderEta()}
+      progElems = [
+        renderDownloadCheckbox(),
+        renderTorrentStatus(),
+        renderProgressBar(),
+        renderPercentProgress(),
+        renderTotalProgress(),
+        renderPeers(),
+        renderSpeeds(),
+        renderEta()
+      ]
+    } else {
+      progElems = [
+        renderDownloadCheckbox(),
+        renderTorrentStatus()
+      ]
+    }
+    elements.push(
+      <div key='progress-info' className='ellipsis'>
+        {progElems}
+      </div>
+    )
+
+    return (<div key='metadata' className='metadata'>{elements}</div>)
+
+    function renderDownloadCheckbox () {
+      const infoHash = torrentSummary.infoHash
+      const isActive = ['downloading', 'seeding'].includes(torrentSummary.status)
+      return (
+        <Checkbox
+          key='download-button'
+          className={'control download ' + torrentSummary.status}
+          style={{
+            display: 'inline-block',
+            width: 32
+          }}
+          iconStyle={{
+            width: 20,
+            height: 20
+          }}
+          checked={isActive}
+          onClick={stopPropagation}
+          onCheck={dispatcher('toggleTorrent', infoHash)} />
+      )
+    }
+
+    function renderProgressBar () {
+      const progress = Math.floor(100 * prog.progress)
+      const styles = {
+        wrapper: {
+          display: 'inline-block',
+          marginRight: 8
+        },
+        progress: {
+          height: 8,
+          width: 30
+        }
+      }
+      return (
+        <div style={styles.wrapper}>
+          <LinearProgress style={styles.progress} mode='determinate' value={progress} />
        </div>
      )
    }

-    return (<div key='metadata' className='metadata'>{elements}</div>)
-
    function renderPercentProgress () {
-      var progress = Math.floor(100 * prog.progress)
+      const progress = Math.floor(100 * prog.progress)
      return (<span key='percent-progress'>{progress}%</span>)
    }

    function renderTotalProgress () {
-      var downloaded = prettyBytes(prog.downloaded)
-      var total = prettyBytes(prog.length || 0)
+      const downloaded = prettyBytes(prog.downloaded)
+      const total = prettyBytes(prog.length || 0)
      if (downloaded === total) {
        return (<span key='total-progress'>{downloaded}</span>)
      } else {
@@ -122,112 +170,78 @@ module.exports = class TorrentList extends React.Component {

    function renderPeers () {
      if (prog.numPeers === 0) return
-      var count = prog.numPeers === 1 ? 'peer' : 'peers'
+      const count = prog.numPeers === 1 ? 'peer' : 'peers'
      return (<span key='peers'>{prog.numPeers} {count}</span>)
    }

-    function renderDownloadSpeed () {
-      if (prog.downloadSpeed === 0) return
-      return (<span key='download'>↓ {prettyBytes(prog.downloadSpeed)}/s</span>)
-    }
-
-    function renderUploadSpeed () {
-      if (prog.uploadSpeed === 0) return
-      return (<span key='upload'>↑ {prettyBytes(prog.uploadSpeed)}/s</span>)
+    function renderSpeeds () {
+      let str = ''
+      if (prog.downloadSpeed > 0) str += ' ↓ ' + prettyBytes(prog.downloadSpeed) + '/s'
+      if (prog.uploadSpeed > 0) str += ' ↑ ' + prettyBytes(prog.uploadSpeed) + '/s'
+      if (str === '') return
+      return (<span key='download'>{str}</span>)
    }

    function renderEta () {
-      var downloaded = prog.downloaded
-      var total = prog.length || 0
-      var missing = total - downloaded
-      var downloadSpeed = prog.downloadSpeed
+      const downloaded = prog.downloaded
+      const total = prog.length || 0
+      const missing = total - downloaded
+      const downloadSpeed = prog.downloadSpeed
      if (downloadSpeed === 0 || missing === 0) return

-      var rawEta = missing / downloadSpeed
-      var hours = Math.floor(rawEta / 3600) % 24
-      var minutes = Math.floor(rawEta / 60) % 60
-      var seconds = Math.floor(rawEta % 60)
+      const rawEta = missing / downloadSpeed
+      const hours = Math.floor(rawEta / 3600) % 24
+      const minutes = Math.floor(rawEta / 60) % 60
+      const seconds = Math.floor(rawEta % 60)

      // Only display hours and minutes if they are greater than 0 but always
      // display minutes if hours is being displayed
-      var hoursStr = hours ? hours + 'h' : ''
-      var minutesStr = (hours || minutes) ? minutes + 'm' : ''
-      var secondsStr = seconds + 's'
+      const hoursStr = hours ? hours + 'h' : ''
+      const minutesStr = (hours || minutes) ? minutes + 'm' : ''
+      const secondsStr = seconds + 's'

-      return (<span>ETA: {hoursStr} {minutesStr} {secondsStr}</span>)
+      return (<span>{hoursStr} {minutesStr} {secondsStr} remaining</span>)
+    }
+
+    function renderTorrentStatus () {
+      let status
+      if (torrentSummary.status === 'paused') {
+        if (!torrentSummary.progress) status = ''
+        else if (torrentSummary.progress.progress === 1) status = 'Not seeding'
+        else status = 'Paused'
+      } else if (torrentSummary.status === 'downloading') {
+        status = 'Downloading'
+      } else if (torrentSummary.status === 'seeding') {
+        status = 'Seeding'
+      } else { // torrentSummary.status is 'new' or something unexpected
+        status = ''
+      }
+      return (<span>{status}</span>)
    }
  }

  // Download button toggles between torrenting (DL/seed) and paused
  // Play button starts streaming the torrent immediately, unpausing if needed
  renderTorrentButtons (torrentSummary) {
-    var infoHash = torrentSummary.infoHash
-
-    var playIcon, playTooltip, playClass
-    if (torrentSummary.playStatus === 'timeout') {
-      playIcon = 'warning'
-      playTooltip = 'Playback timed out. No seeds? No internet? Click to try again.'
-    } else {
-      playIcon = 'play_arrow'
-      playTooltip = 'Start streaming'
-    }
-
-    var downloadIcon, downloadTooltip
-    if (torrentSummary.status === 'seeding') {
-      downloadIcon = 'file_upload'
-      downloadTooltip = 'Seeding. Click to stop.'
-    } else if (torrentSummary.status === 'downloading') {
-      downloadIcon = 'file_download'
-      downloadTooltip = 'Torrenting. Click to stop.'
-    } else {
-      downloadIcon = 'file_download'
-      downloadTooltip = 'Click to start torrenting.'
-    }
+    const infoHash = torrentSummary.infoHash

    // Only show the play/dowload buttons for torrents that contain playable media
-    var playButton, downloadButton, positionElem
-    if (!torrentSummary.error) {
-      downloadButton = (
+    let playButton
+    if (!torrentSummary.error && TorrentPlayer.isPlayableTorrentSummary(torrentSummary)) {
+      playButton = (
        <i
-          key='download-button'
-          className={'button-round icon download ' + torrentSummary.status}
-          title={downloadTooltip}
-          onClick={dispatcher('toggleTorrent', infoHash)}
-        >
-          {downloadIcon}
+          key='play-button'
+          title='Start streaming'
+          className={'icon play'}
+          onClick={dispatcher('playFile', infoHash)}>
+          play_circle_outline
        </i>
      )
-
-      // Do we have a saved position? Show it using a radial progress bar on top
-      // of the play button, unless already showing a spinner there:
-      var willShowSpinner = torrentSummary.playStatus === 'requested'
-      var defaultFile = torrentSummary.files &&
-        torrentSummary.files[torrentSummary.defaultPlayFileIndex]
-      if (defaultFile && defaultFile.currentTime && !willShowSpinner) {
-        var fraction = defaultFile.currentTime / defaultFile.duration
-        positionElem = this.renderRadialProgressBar(fraction, 'radial-progress-large')
-        playClass = 'resume-position'
-      }
-
-      if (TorrentPlayer.isPlayableTorrentSummary(torrentSummary)) {
-        playButton = (
-          <i
-            key='play-button'
-            title={playTooltip}
-            className={'button-round icon play ' + playClass}
-            onClick={dispatcher('playFile', infoHash)}
-          >
-            {playIcon}
-          </i>
-        )
-      }
    }

    return (
-      <div key='buttons' className='buttons'>
-        {positionElem}
+      <div className='torrent-controls'>
        {playButton}
-        {downloadButton}
        <i
          key='delete-button'
          className='icon delete'
@@ -241,9 +255,9 @@ module.exports = class TorrentList extends React.Component {

  // Show files, per-file download status and play buttons, and so on
  renderTorrentDetails (torrentSummary) {
-    var filesElement
+    let filesElement
    if (torrentSummary.error || !torrentSummary.files) {
-      var message = ''
+      let message = ''
      if (torrentSummary.error === 'path-missing') {
        // Special case error: this torrent's download dir or file is missing
        message = 'Missing path: ' + TorrentSummary.getFileOrFolder(torrentSummary)
@@ -264,14 +278,9 @@ module.exports = class TorrentList extends React.Component {
      )
    } else {
      // We do know the files. List them and show download stats for each one
-      var fileRows = torrentSummary.files
+      const fileRows = torrentSummary.files
        .filter((file) => !file.path.includes('/.____padding_file/'))
        .map((file, index) => ({ file, index }))
-        .sort(function (a, b) {
-          if (a.file.name < b.file.name) return -1
-          if (b.file.name < a.file.name) return 1
-          return 0
-        })
        .map((object) => this.renderFileRow(torrentSummary, object.file, object.index))

      filesElement = (
@@ -296,28 +305,28 @@ module.exports = class TorrentList extends React.Component {
  renderFileRow (torrentSummary, file, index) {
    // First, find out how much of the file we've downloaded
    // Are we even torrenting it?
-    var isSelected = torrentSummary.selections && torrentSummary.selections[index]
-    var isDone = false // Are we finished torrenting it?
-    var progress = ''
+    const isSelected = torrentSummary.selections && torrentSummary.selections[index]
+    let isDone = false // Are we finished torrenting it?
+    let progress = ''
    if (torrentSummary.progress && torrentSummary.progress.files &&
        torrentSummary.progress.files[index]) {
-      var fileProg = torrentSummary.progress.files[index]
+      const fileProg = torrentSummary.progress.files[index]
      isDone = fileProg.numPiecesPresent === fileProg.numPieces
      progress = Math.round(100 * fileProg.numPiecesPresent / fileProg.numPieces) + '%'
    }

    // Second, for media files where we saved our position, show how far we got
-    var positionElem
+    let positionElem
    if (file.currentTime) {
      // Radial progress bar. 0% = start from 0:00, 270% = 3/4 of the way thru
      positionElem = this.renderRadialProgressBar(file.currentTime / file.duration)
    }

    // Finally, render the file as a table row
-    var isPlayable = TorrentPlayer.isPlayable(file)
-    var infoHash = torrentSummary.infoHash
-    var icon
-    var handleClick
+    const isPlayable = TorrentPlayer.isPlayable(file)
+    const infoHash = torrentSummary.infoHash
+    let icon
+    let handleClick
    if (isPlayable) {
      icon = 'play_arrow' /* playable? add option to play */
      handleClick = dispatcher('playFile', infoHash, index)
@@ -328,7 +337,7 @@ module.exports = class TorrentList extends React.Component {
        : (e) => e.stopPropagation() // noop if file is not ready
    }
    // TODO: add a css 'disabled' class to indicate that a file cannot be opened/streamed
-    var rowClass = ''
+    let rowClass = ''
    if (!isSelected) rowClass = 'disabled' // File deselected, not being torrented
    if (!isDone && !isPlayable) rowClass = 'disabled' // Can't open yet, can't stream
    return (
@@ -348,16 +357,16 @@ module.exports = class TorrentList extends React.Component {
        </td>
        <td className='col-select'
          onClick={dispatcher('toggleTorrentFile', infoHash, index)}>
-          <i className='icon'>{isSelected ? 'close' : 'add'}</i>
+          <i className='icon deselect-file'>{isSelected ? 'close' : 'add'}</i>
        </td>
      </tr>
    )
  }

  renderRadialProgressBar (fraction, cssClass) {
-    var rotation = 360 * fraction
-    var transformFill = {transform: 'rotate(' + (rotation / 2) + 'deg)'}
-    var transformFix = {transform: 'rotate(' + rotation + 'deg)'}
+    const rotation = 360 * fraction
+    const transformFill = {transform: 'rotate(' + (rotation / 2) + 'deg)'}
+    const transformFix = {transform: 'rotate(' + rotation + 'deg)'}

    return (
      <div key='radial-progress' className={'radial-progress ' + cssClass}>
@@ -376,8 +385,12 @@ module.exports = class TorrentList extends React.Component {
  }
 }

+function stopPropagation (e) {
+  e.stopPropagation()
+}
+
 function getErrorMessage (torrentSummary) {
-  var err = torrentSummary.error
+  const err = torrentSummary.error
  if (err === 'path-missing') {
    return (
      <span>
--- a/src/renderer/webtorrent.js
+++ b/src/renderer/webtorrent.js
@@ -2,26 +2,28 @@
 // process from the main window.
 console.time('init')

-var crypto = require('crypto')
-var deepEqual = require('deep-equal')
-var defaultAnnounceList = require('create-torrent').announceList
-var electron = require('electron')
-var fs = require('fs-extra')
-var musicmetadata = require('musicmetadata')
-var networkAddress = require('network-address')
-var path = require('path')
-var WebTorrent = require('webtorrent')
-var zeroFill = require('zero-fill')
+const crypto = require('crypto')
+const deepEqual = require('deep-equal')
+const defaultAnnounceList = require('create-torrent').announceList
+const electron = require('electron')
+const fs = require('fs')
+const mkdirp = require('mkdirp')
+const musicmetadata = require('musicmetadata')
+const networkAddress = require('network-address')
+const path = require('path')
+const WebTorrent = require('webtorrent')
+const zeroFill = require('zero-fill')

-var crashReporter = require('../crash-reporter')
-var config = require('../config')
-var torrentPoster = require('./lib/torrent-poster')
+const crashReporter = require('../crash-reporter')
+const config = require('../config')
+const {TorrentKeyNotFoundError} = require('./lib/errors')
+const torrentPoster = require('./lib/torrent-poster')

 // Report when the process crashes
 crashReporter.init()

 // Send & receive messages from the main window
-var ipc = electron.ipcRenderer
+const ipc = electron.ipcRenderer

 // Force use of webtorrent trackers on all torrents
 global.WEBTORRENT_ANNOUNCE = defaultAnnounceList
@@ -31,7 +33,7 @@ global.WEBTORRENT_ANNOUNCE = defaultAnnounceList
 /**
 * WebTorrent version.
 */
-var VERSION = require('../../package.json').version
+const VERSION = require('../../package.json').version

 /**
 * Version number in Azureus-style. Generated from major and minor semver version.
@@ -39,7 +41,7 @@ var VERSION = require('../../package.json').version
 *   '0.16.1' -> '0016'
 *   '1.2.5' -> '0102'
 */
-var VERSION_STR = VERSION.match(/([0-9]+)/g)
+const VERSION_STR = VERSION.match(/([0-9]+)/g)
  .slice(0, 2)
  .map((v) => zeroFill(2, v))
  .join('')
@@ -51,25 +53,27 @@ var VERSION_STR = VERSION.match(/([0-9]+)/g)
 * For example:
 *   '-WW0102-'...
 */
-var VERSION_PREFIX = '-WD' + VERSION_STR + '-'
+const VERSION_PREFIX = '-WD' + VERSION_STR + '-'
+
+/**
+ * Generate an ephemeral peer ID each time.
+ */
+const PEER_ID = Buffer.from(VERSION_PREFIX + crypto.randomBytes(9).toString('base64'))

 // Connect to the WebTorrent and BitTorrent networks. WebTorrent Desktop is a hybrid
 // client, as explained here: https://webtorrent.io/faq
-var client = window.client = new WebTorrent({
-  peerId: Buffer.from(VERSION_PREFIX + crypto.randomBytes(6).toString('hex'))
-})
+let client = window.client = new WebTorrent({ peerId: PEER_ID })

 // WebTorrent-to-HTTP streaming sever
-var server = null
+let server = null

 // Used for diffing, so we only send progress updates when necessary
-var prevProgress = null
+let prevProgress = null

 init()

 function init () {
-  client.on('warning', (err) => ipc.send('wt-warning', null, err.message))
-  client.on('error', (err) => ipc.send('wt-error', null, err.message))
+  listenToClientEvents()

  ipc.on('wt-start-torrenting', (e, torrentKey, torrentID, path, fileModtimes, selections) =>
    startTorrenting(torrentKey, torrentID, path, fileModtimes, selections))
@@ -83,8 +87,8 @@ function init () {
    generateTorrentPoster(torrentKey))
  ipc.on('wt-get-audio-metadata', (e, infoHash, index) =>
    getAudioMetadata(infoHash, index))
-  ipc.on('wt-start-server', (e, infoHash, index) =>
-    startServer(infoHash, index))
+  ipc.on('wt-start-server', (e, infoHash) =>
+    startServer(infoHash))
  ipc.on('wt-stop-server', (e) =>
    stopServer())
  ipc.on('wt-select-files', (e, infoHash, selections) =>
@@ -100,12 +104,17 @@ function init () {
  console.timeEnd('init')
 }

-// Starts a given TorrentID, which can be an infohash, magnet URI, etc. Returns WebTorrent object
-// See https://github.com/feross/webtorrent/blob/master/docs/api.md#clientaddtorrentid-opts-function-ontorrent-torrent-
+function listenToClientEvents () {
+  client.on('warning', (err) => ipc.send('wt-warning', null, err.message))
+  client.on('error', (err) => ipc.send('wt-error', null, err.message))
+}
+
+// Starts a given TorrentID, which can be an infohash, magnet URI, etc.
+// Returns a WebTorrent object. See https://git.io/vik9M
 function startTorrenting (torrentKey, torrentID, path, fileModtimes, selections) {
  console.log('starting torrent %s: %s', torrentKey, torrentID)

-  var torrent = client.add(torrentID, {
+  const torrent = client.add(torrentID, {
    path: path,
    fileModtimes: fileModtimes
  })
@@ -116,20 +125,19 @@ function startTorrenting (torrentKey, torrentID, path, fileModtimes, selections)

  // Only download the files the user wants, not necessarily all files
  torrent.once('ready', () => selectFiles(torrent, selections))
-
-  return torrent
 }

 function stopTorrenting (infoHash) {
-  var torrent = client.get(infoHash)
+  console.log('--- STOP TORRENTING: ', infoHash)
+  const torrent = client.get(infoHash)
  if (torrent) torrent.destroy()
 }

 // Create a new torrent, start seeding
 function createTorrent (torrentKey, options) {
  console.log('creating torrent', torrentKey, options)
-  var paths = options.files.map((f) => f.path)
-  var torrent = client.seed(paths, options)
+  const paths = options.files.map((f) => f.path)
+  const torrent = client.seed(paths, options)
  torrent.key = torrentKey
  addTorrentEvents(torrent)
  ipc.send('wt-new-torrent')
@@ -147,22 +155,22 @@ function addTorrentEvents (torrent) {
  torrent.on('done', torrentDone)

  function torrentMetadata () {
-    var info = getTorrentInfo(torrent)
+    const info = getTorrentInfo(torrent)
    ipc.send('wt-metadata', torrent.key, info)

    updateTorrentProgress()
  }

  function torrentReady () {
-    var info = getTorrentInfo(torrent)
+    const info = getTorrentInfo(torrent)
    ipc.send('wt-ready', torrent.key, info)
-    ipc.send('wt-ready-' + torrent.infoHash, torrent.key, info) // TODO: hack
+    ipc.send('wt-ready-' + torrent.infoHash, torrent.key, info)

    updateTorrentProgress()
  }

  function torrentDone () {
-    var info = getTorrentInfo(torrent)
+    const info = getTorrentInfo(torrent)
    ipc.send('wt-done', torrent.key, info)

    updateTorrentProgress()
@@ -195,19 +203,22 @@ function getTorrentFileInfo (file) {
  }
 }

-// Every time we resolve a magnet URI, save the torrent file so that we never
-// have to download it again. Never ask the DHT the same question twice.
+// Every time we resolve a magnet URI, save the torrent file so that we can use
+// it on next startup. Starting with the full torrent metadata will be faster
+// than re-fetching it from peers using ut_metadata.
 function saveTorrentFile (torrentKey) {
-  var torrent = getTorrent(torrentKey)
-  checkIfTorrentFileExists(torrent.infoHash, function (torrentPath, exists) {
-    var fileName = torrent.infoHash + '.torrent'
-    if (exists) {
+  const torrent = getTorrent(torrentKey)
+  const torrentPath = path.join(config.TORRENT_PATH, torrent.infoHash + '.torrent')
+
+  fs.access(torrentPath, fs.constants.R_OK, function (err) {
+    const fileName = torrent.infoHash + '.torrent'
+    if (!err) {
      // We've already saved the file
      return ipc.send('wt-file-saved', torrentKey, fileName)
    }

    // Otherwise, save the .torrent file, under the app config folder
-    fs.mkdir(config.TORRENT_PATH, function (_) {
+    mkdirp(config.TORRENT_PATH, function (_) {
      fs.writeFile(torrentPath, torrent.torrentFile, function (err) {
        if (err) return console.log('error saving torrent file %s: %o', torrentPath, err)
        console.log('saved torrent file %s', torrentPath)
@@ -217,26 +228,17 @@ function saveTorrentFile (torrentKey) {
  })
 }

-// Checks whether we've already resolved a given infohash to a torrent file
-// Calls back with (torrentPath, exists). Logs, does not call back on error
-function checkIfTorrentFileExists (infoHash, cb) {
-  var torrentPath = path.join(config.TORRENT_PATH, infoHash + '.torrent')
-  fs.exists(torrentPath, function (exists) {
-    cb(torrentPath, exists)
-  })
-}
-
 // Save a JPG that represents a torrent.
 // Auto chooses either a frame from a video file, an image, etc
 function generateTorrentPoster (torrentKey) {
-  var torrent = getTorrent(torrentKey)
+  const torrent = getTorrent(torrentKey)
  torrentPoster(torrent, function (err, buf, extension) {
    if (err) return console.log('error generating poster: %o', err)
    // save it for next time
-    fs.mkdirp(config.POSTER_PATH, function (err) {
+    mkdirp(config.POSTER_PATH, function (err) {
      if (err) return console.log('error creating poster dir: %o', err)
-      var posterFileName = torrent.infoHash + extension
-      var posterFilePath = path.join(config.POSTER_PATH, posterFileName)
+      const posterFileName = torrent.infoHash + extension
+      const posterFilePath = path.join(config.POSTER_PATH, posterFileName)
      fs.writeFile(posterFilePath, buf, function (err) {
        if (err) return console.log('error saving poster: %o', err)
        // show the poster
@@ -247,7 +249,7 @@ function generateTorrentPoster (torrentKey) {
 }

 function updateTorrentProgress () {
-  var progress = getTorrentProgress()
+  const progress = getTorrentProgress()
  // TODO: diff torrent-by-torrent, not once for the whole update
  if (prevProgress && deepEqual(progress, prevProgress, {strict: true})) {
    return /* don't send heavy object if it hasn't changed */
@@ -258,19 +260,19 @@ function updateTorrentProgress () {

 function getTorrentProgress () {
  // First, track overall progress
-  var progress = client.progress
-  var hasActiveTorrents = client.torrents.some(function (torrent) {
+  const progress = client.progress
+  const hasActiveTorrents = client.torrents.some(function (torrent) {
    return torrent.progress !== 1
  })

  // Track progress for every file in each torrent
  // TODO: ideally this would be tracked by WebTorrent, which could do it
  // more efficiently than looping over torrent.bitfield
-  var torrentProg = client.torrents.map(function (torrent) {
-    var fileProg = torrent.files && torrent.files.map(function (file, index) {
-      var numPieces = file._endPiece - file._startPiece + 1
-      var numPiecesPresent = 0
-      for (var piece = file._startPiece; piece <= file._endPiece; piece++) {
+  const torrentProg = client.torrents.map(function (torrent) {
+    const fileProg = torrent.files && torrent.files.map(function (file, index) {
+      const numPieces = file._endPiece - file._startPiece + 1
+      let numPiecesPresent = 0
+      for (let piece = file._startPiece; piece <= file._endPiece; piece++) {
        if (torrent.bitfield.get(piece)) numPiecesPresent++
      }
      return {
@@ -301,28 +303,28 @@ function getTorrentProgress () {
  }
 }

-function startServer (infoHash, index) {
-  var torrent = client.get(infoHash)
-  if (torrent.ready) startServerFromReadyTorrent(torrent, index)
-  else torrent.once('ready', () => startServerFromReadyTorrent(torrent, index))
+function startServer (infoHash) {
+  const torrent = client.get(infoHash)
+  if (torrent.ready) startServerFromReadyTorrent(torrent)
+  else torrent.once('ready', () => startServerFromReadyTorrent(torrent))
 }

-function startServerFromReadyTorrent (torrent, index, cb) {
+function startServerFromReadyTorrent (torrent, cb) {
  if (server) return

  // start the streaming torrent-to-http server
  server = torrent.createServer()
  server.listen(0, function () {
-    var port = server.address().port
-    var urlSuffix = ':' + port + '/' + index
-    var info = {
+    const port = server.address().port
+    const urlSuffix = ':' + port
+    const info = {
      torrentKey: torrent.key,
      localURL: 'http://localhost' + urlSuffix,
      networkURL: 'http://' + networkAddress() + urlSuffix
    }

    ipc.send('wt-server-running', info)
-    ipc.send('wt-server-' + torrent.infoHash, info) // TODO: hack
+    ipc.send('wt-server-' + torrent.infoHash, info)
  })
 }

@@ -333,23 +335,28 @@ function stopServer () {
 }

 function getAudioMetadata (infoHash, index) {
-  var torrent = client.get(infoHash)
-  var file = torrent.files[index]
+  const torrent = client.get(infoHash)
+  const file = torrent.files[index]
  musicmetadata(file.createReadStream(), function (err, info) {
-    if (err) return
-    console.log('got audio metadata for %s: %o', file.name, info)
-    ipc.send('wt-audio-metadata', infoHash, index, info)
+    if (err) return console.log('error getting audio metadata for ' + infoHash + ':' + index, err)
+    const { artist, album, albumartist, title, year, track, disk, genre } = info
+    const importantInfo = { artist, album, albumartist, title, year, track, disk, genre }
+    console.log('got audio metadata for %s: %o', file.name, importantInfo)
+    ipc.send('wt-audio-metadata', infoHash, index, importantInfo)
  })
 }

 function selectFiles (torrentOrInfoHash, selections) {
  // Get the torrent object
-  var torrent
+  let torrent
  if (typeof torrentOrInfoHash === 'string') {
    torrent = client.get(torrentOrInfoHash)
  } else {
    torrent = torrentOrInfoHash
  }
+  if (!torrent) {
+    throw new Error('selectFiles: missing torrent ' + torrentOrInfoHash)
+  }

  // Selections not specified?
  // Load all files. We still need to replace the default whole-torrent
@@ -369,8 +376,8 @@ function selectFiles (torrentOrInfoHash, selections) {
  torrent.deselect(0, torrent.pieces.length - 1, false)

  // Add selections (individual files)
-  for (var i = 0; i < selections.length; i++) {
-    var file = torrent.files[i]
+  for (let i = 0; i < selections.length; i++) {
+    const file = torrent.files[i]
    if (selections[i]) {
      file.select()
    } else {
@@ -383,11 +390,25 @@ function selectFiles (torrentOrInfoHash, selections) {
 // Gets a WebTorrent handle by torrentKey
 // Throws an Error if we're not currently torrenting anything w/ that key
 function getTorrent (torrentKey) {
-  var ret = client.torrents.find((x) => x.key === torrentKey)
-  if (!ret) throw new Error('missing torrent key ' + torrentKey)
+  const ret = client.torrents.find((x) => x.key === torrentKey)
+  if (!ret) throw new TorrentKeyNotFoundError(torrentKey)
  return ret
 }

 function onError (err) {
  console.log(err)
 }
+
+// TODO: remove this once the following bugs are fixed:
+// https://bugs.chromium.org/p/chromium/issues/detail?id=490143
+// https://github.com/electron/electron/issues/7212
+window.testOfflineMode = function () {
+  console.log('Test, going OFFLINE')
+  client = window.client = new WebTorrent({
+    peerId: PEER_ID,
+    tracker: false,
+    dht: false,
+    webSeeds: false
+  })
+  listenToClientEvents()
+}
--- a/static/NextTrackThumbnailBarButton.png
+++ b/static/NextTrackThumbnailBarButton.png
--- a/static/PreviousTrackThumbnailBarButton.png
+++ b/static/PreviousTrackThumbnailBarButton.png
--- a/static/about.html
+++ b/static/about.html
@@ -32,6 +32,7 @@
    <p>
      Version <script>document.write(require('../package.json').version)</script>
      (<script>document.write(require('webtorrent/package.json').version)</script>)
+      (<script>document.write(process.arch === 'x64' ? '64-bit' : '32-bit')</script>)
    </p>
    <p><script>document.write(require('../config').APP_COPYRIGHT)</script></p>
  </body>
--- a/static/appdmg.png
+++ b/static/appdmg.png
--- a/static/appdmg@2x.png
+++ b/static/appdmg@2x.png
--- a/static/main.css
+++ b/static/main.css
@@ -265,10 +265,6 @@ table {
  font-weight: bold;
 }

-.open-torrent-address-modal input {
-  width: 100%;
-}
-
 .create-torrent {
  padding: 10px 25px;
  overflow: hidden;
@@ -276,6 +272,7 @@ table {

 .create-torrent .torrent-attribute {
  white-space: nowrap;
+  margin: 8px 0;
 }

 .create-torrent .torrent-attribute>* {
@@ -283,13 +280,12 @@ table {
 }

 .create-torrent .torrent-attribute label {
-  width: 60px;
-  margin-right: 10px;
+  width: 100px;
  vertical-align: top;
 }

 .create-torrent .torrent-attribute>div {
-  width: calc(100% - 90px);
+  width: calc(100% - 100px);
 }

 .create-torrent .torrent-attribute div {
@@ -298,18 +294,6 @@ table {
  text-overflow: ellipsis;
 }

-.create-torrent .torrent-attribute textarea {
-  width: calc(100% - 80px);
-  height: 80px;
-  color: #eee;
-  background-color: transparent;
-  line-height: 1.5;
-  font-size: 14px;
-  font-family: inherit;
-  border-radius: 2px;
-  padding: 4px 6px;
-}
-
 /*
 * BUTTONS
 */
@@ -325,13 +309,13 @@ i:not(.disabled):hover { /* Show they're clickable without pointer: cursor */
  -webkit-filter: brightness(1.3);
 }

-.button-round { /* Circular icon buttons, used on <i> tags */
-  width: 40px;
-  height: 40px;
-  border-radius: 20px;
-  font-size: 22px;
-  transition: all 0.1s ease-out;
-  text-align: center;
+/*
+ * INPUTS
+ */
+input,
+textarea,
+.control {
+  font-size: 14px !important;
 }

 /*
@@ -354,26 +338,18 @@ i:not(.disabled):hover { /* Show they're clickable without pointer: cursor */
 }

 .torrent:not(:last-child) {
-  border-bottom: 1px solid rgb(20, 20, 20);
-}
-
-.torrent:hover {
-  -webkit-filter: brightness(1.1);
+  border-bottom: 1px solid #282828;
 }

 .torrent .metadata {
  position: absolute;
-  top: 25px;
+  top: 20px;
  left: 15px;
  right: 15px;
-  width: calc(100% - 40px);
+  width: calc(100% - 30px);
  text-shadow: rgba(0, 0, 0, 0.5) 0 0 4px;
 }

-.torrent:hover .metadata {
-  width: calc(100% - 150px);
-}
-
 .torrent .metadata span:not(:last-child)::after {
  content: ' • ';
  opacity: 0.7;
@@ -381,79 +357,34 @@ i:not(.disabled):hover { /* Show they're clickable without pointer: cursor */
  padding-right: 4px;
 }

-.torrent .buttons {
-  position: absolute;
-  top: 29px;
-  right: 10px;
-  align-items: center;
+.torrent:hover .metadata {
+  width: calc(100% - 120px);
+}
+
+.torrent .torrent-controls {
  display: none;
 }

-.torrent:hover .buttons {
-  display: flex;
+.torrent:hover .torrent-controls {
+  display: block;
 }

-.torrent .buttons > * {
-  margin-left: 6px; /* space buttons apart */
+.torrent .play {
+  position: absolute;
+  top: 23px;
+  right: 45px;
+  font-size: 55px;
 }

-.torrent .buttons .download {
-  background-color: #2233BB;
-  width: 28px;
-  height: 28px;
-  border-radius: 14px;
-  font-size: 18px;
-  padding-top: 6px;
+.torrent .delete {
+  position: absolute;
+  top: 38px;
+  right: 12px;
 }

-.torrent .buttons .download.downloading {
-  color: #44dd44;
-}
-
-.torrent .buttons .download.seeding {
-  color: #44dd44;
-}
-
-.torrent .buttons .play {
-  padding-top: 10px;
-  background-color: #F44336;
-}
-
-.torrent.timeout .play {
-  padding-top: 8px;
-}
-
-.torrent.requested .play,
-.loading-spinner {
-  border-top: 6px solid rgba(255, 255, 255, 0.2);
-  border-right: 6px solid rgba(255, 255, 255, 0.2);
-  border-bottom: 6px solid rgba(255, 255, 255, 0.2);
-  border-left: 6px solid #ffffff;
-  border-radius: 50%;
-  color: transparent;
-  animation: load8 1.1s infinite linear;
-}
-
-@keyframes load8 {
-  0% {
-    transform: rotate(0deg);
-  }
-  100% {
-    transform: rotate(360deg);
-  }
-}
-
-.torrent .buttons .play.resume-position {
-  position: relative;
-  -webkit-clip-path: circle(18px at center);
-}
-
-.torrent .buttons .delete {
-  opacity: 0.5;
-}
-
-.torrent .buttons .delete:hover {
-  opacity: 0.7;
+.torrent .download {
+  vertical-align: -0.4em;
+  margin-left: -2px;
 }

 .torrent .buttons .radial-progress {
@@ -461,9 +392,27 @@ i:not(.disabled):hover { /* Show they're clickable without pointer: cursor */
 }

 .torrent .name {
-  font-size: 18px;
+  font-size: 20px;
  font-weight: bold;
  line-height: 1.5em;
+  margin-bottom: 6px;
+}
+
+.torrent hr {
+  position: absolute;
+  bottom: 5px;
+  left: calc(50% - 20px);
+  width: 40px;
+  height: 1px;
+  background: #ccc;
+  display: none;
+  margin: 0;
+  padding: 0;
+  border: none;
+}
+
+.torrent:hover hr {
+  display: block;
 }

 /*
@@ -517,6 +466,7 @@ body.drag .app::after {
 /*
 * TORRENT LIST: EXPANDED TORRENT DETAILS
 */
+
 .torrent.selected {
  height: auto;
 }
@@ -540,10 +490,6 @@ body.drag .app::after {
  height: 28px;
 }

-.torrent-details tr:hover {
-  background-color: rgba(200, 200, 200, 0.3);
-}
-
 .torrent-details td {
  overflow: hidden;
  padding: 0;
@@ -640,11 +586,15 @@ body.drag .app::after {
  opacity: 1;
 }

-.player .controls .play-pause {
+.player .controls .icon.disabled {
+  opacity: 0.3;
+}
+
+.player .controls .icon.skip-previous,
+.player .controls .icon.play-pause,
+.player .controls .icon.skip-next {
  font-size: 28px;
-  margin-top: 5px;
-  margin-right: 10px;
-  margin-left: 15px;
+  margin: 5px;
 }

 .player .controls .volume-slider {
@@ -686,14 +636,6 @@ body.drag .app::after {
  cursor: none;
 }

-/* TODO: find better way to handle this (that also
- * keeps the header visible too).
- */
-.app.hide-video-controls .player .controls:hover {
-  opacity: 1;
-  cursor: default;
-}
-
 /* invisible click target for scrubbing */
 .player .controls .scrub-bar {
  position: absolute;
--- a/static/main.html
+++ b/static/main.html
@@ -3,7 +3,7 @@
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
-    <title>WebTorrent Desktop</title>
+    <title>Main Window</title>
    <link rel="stylesheet" href="main.css">
  </head>
  <body>
--- a/static/sound/add.wav
+++ b/static/sound/add.wav
--- a/static/sound/disable.wav
+++ b/static/sound/disable.wav
--- a/static/sound/done.wav
+++ b/static/sound/done.wav
--- a/static/sound/enable.wav
+++ b/static/sound/enable.wav
--- a/static/sound/error.wav
+++ b/static/sound/error.wav
--- a/static/sound/play.wav
+++ b/static/sound/play.wav
--- a/static/webtorrent.html
+++ b/static/webtorrent.html
@@ -3,7 +3,7 @@
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
-    <title>WebTorrent Desktop</title>
+    <title>WebTorrent Hidden Window</title>
    <style>
      body {
        background-color: #282828;
--- a/static/wiredCd.torrent
+++ b/static/wiredCd.torrent
--- a/test/config.js
+++ b/test/config.js
@@ -0,0 +1,15 @@
+const path = require('path')
+
+const TEMP_DIR = process.platform === 'win32' ? 'C:\\Windows\\Temp' : '/tmp'
+const TEST_DIR = path.join(TEMP_DIR, 'WebTorrentTest')
+const TEST_DIR_DOWNLOAD = path.join(TEST_DIR, 'Downloads')
+const TEST_DIR_DESKTOP = path.join(TEST_DIR, 'Desktop')
+
+module.exports = {
+  TORRENT_FILES: [path.join(__dirname, 'resources', '1.torrent')],
+  SEED_FILES: [path.join(TEST_DIR_DESKTOP, 'tmp.jpg')],
+  SAVED_TORRENT_FILE: path.join(TEST_DIR_DESKTOP, 'saved.torrent'),
+  TEST_DIR,
+  TEST_DIR_DOWNLOAD,
+  TEST_DIR_DESKTOP
+}
--- a/test/index.js
+++ b/test/index.js
@@ -0,0 +1,19 @@
+const test = require('tape')
+const setup = require('./setup')
+
+test.onFinish(setup.deleteTestDataDir)
+
+test('app runs', function (t) {
+  t.timeoutAfter(10e3)
+  setup.resetTestDataDir()
+  const app = setup.createApp()
+  setup.waitForLoad(app, t)
+    .then(() => setup.screenshotCreateOrCompare(app, t, 'app-basic'))
+    .then(() => setup.endTest(app, t),
+          (err) => setup.endTest(app, t, err || 'error'))
+})
+
+require('./test-torrent-list')
+require('./test-add-torrent')
+require('./test-video')
+require('./test-audio')
--- a/test/mocks.js
+++ b/test/mocks.js
@@ -0,0 +1,15 @@
+const electron = require('electron')
+const config = require('./config')
+
+console.log('Mocking electron.dialog.showOpenDialog...')
+electron.dialog.showOpenDialog = function (win, opts, cb) {
+  const ret = /select.*torrent file/i.test(opts.title)
+    ? config.TORRENT_FILES
+    : config.SEED_FILES
+  cb(ret)
+}
+
+console.log('Mocking electron.remote.dialog.showSaveDialog...')
+electron.dialog.showSaveDialog = function (win, opts, cb) {
+  cb(config.SAVED_TORRENT_FILE)
+}
--- a/Show More
+++ b/Show More