fix(Chrome): Prevent chrome from killing our worker while it's syncing

marcelklehr · marcelklehr · commit 713821947eb2 · 2025-12-12T16:00:47.000+01:00
fixes #2096 Signed-off-by: Marcel Klehr <mklehr@gmx.net>
diff --git a/gulpfile.js b/gulpfile.js
@@ -118,7 +118,7 @@ const js = async function() {
 const html = function(statsJson) {
   fs.mkdirSync('dist/html/', { recursive: true })
   let html, scripts, bgScript, addition
-  ;['index.html', 'options.html', 'background.html', 'test.html'].forEach(htmlFile => {
+  ;['index.html', 'options.html', 'background.html', 'test.html', 'offscreen.html'].forEach(htmlFile => {
     switch (htmlFile) {
       case 'index.html':
         html = fs.readFileSync('html/' + htmlFile, 'utf8')
@@ -139,6 +139,10 @@ const html = function(statsJson) {
         html = html.replace('{{ scripts }}', scripts)
         fs.writeFileSync('dist/html/' + htmlFile, html)
         break
+      case 'offscreen.html':
+        html = fs.readFileSync('html/' + htmlFile, 'utf8')
+        fs.writeFileSync('dist/html/' + htmlFile, html)
+        break
       case 'background.html':
         html = fs.readFileSync('html/' + htmlFile, 'utf8')
         scripts = statsJson.entrypoints['background-script'].assets.map(asset => `<script src="../js/${asset.name}"></script>`).join('\n')
diff --git a/html/offscreen.html b/html/offscreen.html
@@ -0,0 +1,2 @@
+<!DOCTYPE html>
+<script src="../js/offscreen.js"></script>
diff --git a/manifest.chrome.json b/manifest.chrome.json
@@ -12,7 +12,7 @@
 
   "default_locale": "en",
 
-  "permissions": ["alarms", "bookmarks", "storage", "unlimitedStorage", "tabs", "tabGroups", "identity"],
+  "permissions": ["alarms", "bookmarks", "storage", "unlimitedStorage", "tabs", "tabGroups", "identity", "offscreen"],
   "optional_permissions": ["history"],
   "host_permissions": [
     "*://*/*"
diff --git a/src/entries/offscreen.js b/src/entries/offscreen.js
@@ -0,0 +1,24 @@
+// eslint-disable-next-line no-use-before-define
+if (typeof chrome === 'undefined') {
+  var chrome = {}
+}
+// Keep the connection alive by sending periodic messages
+setInterval(() => {
+  // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+  // @ts-ignore
+  chrome.runtime.sendMessage({
+    type: 'ping-service-worker'
+  }).catch((err) => {
+    console.debug('Failed to ping service worker:', err)
+  })
+}, 25000) // Send message every 25 seconds
+
+// Listen for messages from service worker
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-ignore
+chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
+  if (message.type === 'sync-progress') {
+    sendResponse({ success: true })
+  }
+  return true // Keep message channel open
+})
diff --git a/src/lib/Account.ts b/src/lib/Account.ts
@@ -15,6 +15,7 @@ import { setUser, setContext, withScope, captureException } from '@sentry/browse
 import AsyncLock from 'async-lock'
 import CachingTreeWrapper from './CachingTreeWrapper'
 import { UnexpectedFolderPathError } from '../errors/Error'
+import { createOffscreen, destroyOffscreen } from './offscreen'
 
 declare const DEBUG: boolean
 
@@ -84,6 +85,7 @@ export default class Account {
   protected localTabs: TLocalTree
   protected lockTimeout: number
 
+  private offscreenPingInterval: any = null
   private localCachingResource: CachingTreeWrapper
 
   constructor(id:string, storageAdapter:IAccountStorage, serverAdapter: TAdapter, treeAdapter:TLocalTree) {
@@ -191,6 +193,16 @@ export default class Account {
         if (oldPath && newPath !== oldPath) {
           throw new UnexpectedFolderPathError(oldPath, newPath)
         }
+
+        // eslint-disable-next-line no-undef
+        if (self.constructor.name === 'ServiceWorkerGlobalScope' || (typeof chrome !== 'undefined' && 'offscreen' in chrome)) {
+          // Create an offscreen page in chrome and ping it regularly to prevent this worker from getting killed
+          await createOffscreen()
+          this.offscreenPingInterval = setInterval(() => {
+            // eslint-disable-next-line no-undef
+            chrome.runtime.sendMessage({type: 'sync-progress'})
+          }, 20000)
+        }
       }
 
       if (this.server.onSyncStart) {
@@ -389,6 +401,12 @@ export default class Account {
         await this.init()
       }
     }
+    // eslint-disable-next-line no-undef
+    if (self.constructor.name === 'ServiceWorkerGlobalScope' || (typeof chrome !== 'undefined' && 'offscreen' in chrome)) {
+      // We destroy the offscreen page when the sync is done to allow the worker to be killed
+      await destroyOffscreen()
+    }
+    clearInterval(this.offscreenPingInterval)
     this.syncProcess = null
     this.localCachingResource = null
     await Logger.persist()
@@ -422,6 +440,10 @@ export default class Account {
     if (!this.syncProcess) {
       return
     }
+    if (self.constructor.name === 'ServiceWorkerGlobalScope') {
+      // eslint-disable-next-line no-undef
+      chrome.runtime.sendMessage({ type: 'sync-progress' })
+    }
     if (actionsDone) {
       if (this.server.isAtomic()) {
         const cache = (await this.localCachingResource.getCacheTree()).clone(false)
diff --git a/src/lib/offscreen.ts b/src/lib/offscreen.ts
@@ -0,0 +1,15 @@
+import browserApi from './browser-api'
+export async function createOffscreen() {
+  if (await browserApi.offscreen.hasDocument()) return
+
+  await browserApi.offscreen.createDocument({
+    url: '/dist/html/offscreen.html',
+    reasons: ['WORKERS'],
+    justification: 'In order to sync your bookmarks uninterrupted without displaying a visible window.'
+  })
+}
+
+export async function destroyOffscreen() {
+  if (!(await browserApi.offscreen.hasDocument())) return
+  await browserApi.offscreen.closeDocument()
+}
diff --git a/webpack.common.js b/webpack.common.js
@@ -14,6 +14,7 @@ module.exports = {
     options: path.join(__dirname, 'src', 'entries', 'options.js'),
     test: path.join(__dirname, 'src', 'entries', 'test.js'),
     native: path.join(__dirname, 'src', 'entries', 'native.js'),
+    offscreen: path.join(__dirname, 'src', 'entries', 'offscreen.js'),
   },
   output: {
     path: path.resolve(__dirname, 'dist', 'js'),

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+<!DOCTYPE html>`
	`2`	`+<script src="../js/offscreen.js"></script>`