fix: grant clipboard-write permission to webview sessions (fixes #154)

The Copy button in the Open WebUI interface silently failed on
GNOME/Wayland/Flatpak because the webview session permission handlers
did not include 'clipboard-sanitized-write'. Electron denied the
navigator.clipboard.writeText() call, but the web app saw no error
and briefly showed 'Copied' without actually writing to the clipboard.

Added 'clipboard-sanitized-write' to both permission handler whitelists:
- Per-connection content window handler
- session-created handler for webview partition sessions

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.0.13] - 2026-04-27
+
+### Fixed
+
+- **Copy Button on Linux (GNOME/Wayland/Flatpak).** Fixed the "Copy" button in the Open WebUI interface not actually writing to the system clipboard on Linux. The webview session was missing the `clipboard-sanitized-write` permission required by Electron for `navigator.clipboard.writeText()` to work.
+
 ## [0.0.12] - 2026-04-25
 
 ### Added

package.json

@@ -1,6 +1,6 @@
 {
   "name": "open-webui",
-  "version": "0.0.12",
+  "version": "0.0.13",
   "license": "AGPL-3.0",
   "description": "Open WebUI Desktop",
   "main": "./out/main/index.js",

src/main/index.ts

@@ -737,7 +737,7 @@ function createContentWindow(url: string, connectionId: string): BrowserWindow {
   session
     .fromPartition(`persist:connection-${connectionId}`)
     .setPermissionRequestHandler((_webContents, permission, callback) => {
-      const allowedPermissions = ['media', 'mediaKeySystem', 'notifications']
+      const allowedPermissions = ['media', 'mediaKeySystem', 'notifications', 'clipboard-sanitized-write']
       callback(allowedPermissions.includes(permission))
     })
 
@@ -1213,7 +1213,7 @@ if (!gotTheLock) {
       // Grant media / notification permissions for webview partition sessions
       // so that auth flows, media capture, and notifications work correctly.
       newSession.setPermissionRequestHandler((_webContents, permission, callback) => {
-        const allowed = ['media', 'mediaKeySystem', 'notifications', 'clipboard-read']
+        const allowed = ['media', 'mediaKeySystem', 'notifications', 'clipboard-read', 'clipboard-sanitized-write']
         callback(allowed.includes(permission))
       })
     })