fix(desktop): guard link-title readTitle against destroyed windows

Grace and timeout timers in runRenderTitleJob can call getTitle after
finish() tears down the hidden BrowserWindow, throwing in the main
process when the Artifacts page resolves many link titles concurrently.

apps/desktop/electron/link-title-window.cjs

@@ -49,4 +49,23 @@ function guardLinkTitleSession(partitionSession) {
   }
 }
 
-module.exports = { createLinkTitleWindow, guardLinkTitleSession, linkTitleWindowOptions }
+// Read the page title from a title-fetch window. Callers schedule this from
+// timers that can fire after finish() destroys the window, so every access must
+// guard isDestroyed and swallow Electron's "Object has been destroyed" throws.
+function readLinkTitleWindowTitle(window) {
+  try {
+    if (!window || window.isDestroyed()) return ''
+    const contents = window.webContents
+    if (!contents || contents.isDestroyed()) return ''
+    return contents.getTitle() || ''
+  } catch {
+    return ''
+  }
+}
+
+module.exports = {
+  createLinkTitleWindow,
+  guardLinkTitleSession,
+  linkTitleWindowOptions,
+  readLinkTitleWindowTitle
+}

apps/desktop/electron/link-title-window.test.cjs

@@ -1,7 +1,12 @@
 const assert = require('node:assert/strict')
 const test = require('node:test')
 
-const { createLinkTitleWindow, guardLinkTitleSession, linkTitleWindowOptions } = require('./link-title-window.cjs')
+const {
+  createLinkTitleWindow,
+  guardLinkTitleSession,
+  linkTitleWindowOptions,
+  readLinkTitleWindowTitle
+} = require('./link-title-window.cjs')
 
 function makeFakeBrowserWindow() {
   const calls = { audioMuted: [] }
@@ -66,3 +71,44 @@ test('guardLinkTitleSession cancels downloads triggered by the title-fetch windo
 test('guardLinkTitleSession is a no-op when session.on throws', () => {
   assert.doesNotThrow(() => guardLinkTitleSession({ on() { throw new Error() } }))
 })
+
+test('readLinkTitleWindowTitle returns empty for missing or destroyed windows', () => {
+  assert.equal(readLinkTitleWindowTitle(null), '')
+  assert.equal(readLinkTitleWindowTitle(undefined), '')
+  assert.equal(readLinkTitleWindowTitle({ isDestroyed: () => true }), '')
+})
+
+test('readLinkTitleWindowTitle returns empty when webContents is destroyed', () => {
+  const window = {
+    isDestroyed: () => false,
+    webContents: { isDestroyed: () => true, getTitle: () => 'Should Not Read' }
+  }
+
+  assert.equal(readLinkTitleWindowTitle(window), '')
+})
+
+test('readLinkTitleWindowTitle swallows getTitle throws after teardown', () => {
+  const window = {
+    isDestroyed: () => false,
+    webContents: {
+      isDestroyed: () => false,
+      getTitle: () => {
+        throw new Error('Object has been destroyed')
+      }
+    }
+  }
+
+  assert.equal(readLinkTitleWindowTitle(window), '')
+})
+
+test('readLinkTitleWindowTitle returns trimmed page title', () => {
+  const window = {
+    isDestroyed: () => false,
+    webContents: {
+      isDestroyed: () => false,
+      getTitle: () => 'Example Domain'
+    }
+  }
+
+  assert.equal(readLinkTitleWindowTitle(window), 'Example Domain')
+})

apps/desktop/electron/main.cjs

@@ -36,7 +36,11 @@ const {
   SESSION_WINDOW_MIN_WIDTH
 } = require('./session-windows.cjs')
 const { canImportHermesCli, verifyHermesCli } = require('./backend-probes.cjs')
-const { createLinkTitleWindow, guardLinkTitleSession } = require('./link-title-window.cjs')
+const {
+  createLinkTitleWindow,
+  guardLinkTitleSession,
+  readLinkTitleWindowTitle
+} = require('./link-title-window.cjs')
 const { probeGatewayWebSocket } = require('./gateway-ws-probe.cjs')
 const { adoptServedDashboardToken } = require('./dashboard-token.cjs')
 const { waitForDashboardPortAnnouncement } = require('./backend-ready.cjs')
@@ -3557,13 +3561,13 @@ function runRenderTitleJob(rawUrl) {
       return finish('')
     }
 
-    const readTitle = () => window?.webContents?.getTitle?.() || ''
+    const finishWithTitle = () => finish(readLinkTitleWindowTitle(window))
     const scheduleGrace = () => {
       if (graceTimer) clearTimeout(graceTimer)
-      graceTimer = setTimeout(() => finish(readTitle()), RENDER_TITLE_GRACE_MS)
+      graceTimer = setTimeout(finishWithTitle, RENDER_TITLE_GRACE_MS)
     }
 
-    hardTimer = setTimeout(() => finish(readTitle()), RENDER_TITLE_TIMEOUT_MS)
+    hardTimer = setTimeout(finishWithTitle, RENDER_TITLE_TIMEOUT_MS)
 
     window.webContents.setUserAgent(TITLE_USER_AGENT)
     window.webContents.on('page-title-updated', scheduleGrace)