diff --git a/frontend/src/lib/components/ShareModal.svelte b/frontend/src/lib/components/ShareModal.svelte
index a8eeeeb9d1..e4dc7df614 100644
--- a/frontend/src/lib/components/ShareModal.svelte
+++ b/frontend/src/lib/components/ShareModal.svelte
@@ -1,6 +1,4 @@
 <script lang="ts">
-	import { run } from 'svelte/legacy'
-
 	import TableCustom from './TableCustom.svelte'
 
 	import { GroupService, UserService, GranularAclService } from '$lib/gen'
@@ -42,7 +40,9 @@
 	let ownerKind: 'user' | 'group' = $state('user')
 	let owner: string = $state('')
 
-	let newOwner: string = $state('')
+	let newOwner: string = $derived.by(
+		() => owner && [ownerKind === 'group' ? 'g' : 'u', owner].join('/')
+	)
 	let write: boolean = false
 	let acls: [string, boolean][] = $state([])
 	let groups: String[] = $state([])
@@ -50,10 +50,6 @@
 
 	let drawer: Drawer | undefined = $state()
 
-	run(() => {
-		newOwner = [ownerKind === 'group' ? 'g' : 'u', owner].join('/')
-	})
-
 	let own = $state(false)
 	export async function openDrawer(newPath: string, kind_l: Kind) {
 		path = newPath
@@ -145,7 +141,9 @@
 								bind:value={owner}
 							/>
 						{/key}
-						<Button size="sm" on:click={() => addAcl(newOwner, write)}>Add permission</Button>
+						<Button size="sm" disabled={!newOwner} on:click={() => addAcl(newOwner, write)}
+							>Add permission</Button
+						>
 					</div>
 				{/if}
 				<TableCustom>