Prefer const over let

src/renderer/lib/state.js

@@ -236,7 +236,7 @@ function saveImmediate (state, cb) {
     .filter((x) => x.infoHash)
     .map(function (x) {
       const torrent = {}
-      for (let key in x) {
+      for (const key in x) {
         if (key === 'progress' || key === 'torrentKey') {
           continue // Don't save progress info or key for the webtorrent process
         }

src/renderer/lib/telemetry.js

@@ -98,7 +98,7 @@ function getSystemInfo () {
 function getTorrentStats (state) {
   const count = state.saved.torrents.length
   let sizeMB = 0
-  let byStatus = {
+  const byStatus = {
     new: { count: 0, sizeMB: 0 },
     downloading: { count: 0, sizeMB: 0 },
     seeding: { count: 0, sizeMB: 0 },

src/renderer/lib/torrent-poster.js

@@ -98,7 +98,7 @@ function scoreAudioCoverFile (imgFile) {
     spectrogram: -80
   }
 
-  for (let keyword in relevanceScore) {
+  for (const keyword in relevanceScore) {
     if (fileName === keyword) {
       return relevanceScore[keyword]
     }