fix(desktop): keep oauth popups alive on redirect aborts and blank loads

Toutiao's wap_login redirect chain raises ERR_ABORTED (-3) without the
literal symbol in the message, so the previous regex fell through to the
fallback error page. Now match the numeric form too, and add a 7s blank-
page watchdog that auto-reloads stuck "Loading..." popups once per fresh
navigation.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/desktop-client/src/main/external-window.ts

@@ -2,16 +2,95 @@ import type { BrowserWindow } from 'electron/main'
 
 import { STANDARD_USER_AGENT } from './user-agent'
 
-const ignoredNavigationFailurePattern = /ERR_ABORTED|ERR_BLOCKED_BY_CLIENT/i
+const ignoredNavigationFailurePattern = /ERR_ABORTED|ERR_BLOCKED_BY_CLIENT|\((-3|-20)\) loading/i
 const errorPagePrefix = 'data:text/html'
 
+const BLANK_PAGE_PROBE_DELAY_MS = 7_000
+const BLANK_PAGE_NODE_THRESHOLD = 3
+const BLANK_PAGE_TEXT_THRESHOLD = 5
+
 interface WindowNavigationState {
   readyForDetection: boolean
   lastMainFrameError: string | null
+  blankPageWatchdog: NodeJS.Timeout | null
+  blankPageRetried: boolean
+  context: string
 }
 
 const navigationStateRegistry = new WeakMap<BrowserWindow, WindowNavigationState>()
 
+function clearBlankPageWatchdog(state: WindowNavigationState): void {
+  if (state.blankPageWatchdog) {
+    clearTimeout(state.blankPageWatchdog)
+    state.blankPageWatchdog = null
+  }
+}
+
+async function probePageBodyShape(
+  window: BrowserWindow,
+): Promise<{ nodeCount: number; textLength: number; readyState: string } | null> {
+  if (window.isDestroyed()) {
+    return null
+  }
+  try {
+    return (await window.webContents.executeJavaScript(
+      `(() => ({
+        nodeCount: document.body ? document.body.querySelectorAll('*').length : 0,
+        textLength: document.body ? (document.body.innerText || '').trim().length : 0,
+        readyState: document.readyState,
+      }))()`,
+      true,
+    )) as { nodeCount: number; textLength: number; readyState: string }
+  } catch {
+    return null
+  }
+}
+
+function scheduleBlankPageWatchdog(window: BrowserWindow, state: WindowNavigationState): void {
+  clearBlankPageWatchdog(state)
+
+  state.blankPageWatchdog = setTimeout(() => {
+    state.blankPageWatchdog = null
+    if (window.isDestroyed()) {
+      return
+    }
+
+    const currentURL = window.webContents.getURL()
+    if (currentURL.startsWith(errorPagePrefix) || currentURL === 'about:blank') {
+      return
+    }
+
+    void probePageBodyShape(window).then((shape) => {
+      if (!shape || window.isDestroyed()) {
+        return
+      }
+
+      const looksBlank =
+        shape.nodeCount < BLANK_PAGE_NODE_THRESHOLD &&
+        shape.textLength < BLANK_PAGE_TEXT_THRESHOLD
+
+      if (!looksBlank) {
+        return
+      }
+
+      if (state.blankPageRetried) {
+        console.warn(`[desktop-window] ${state.context} still blank after auto-reload`, {
+          url: currentURL,
+          ...shape,
+        })
+        return
+      }
+
+      state.blankPageRetried = true
+      console.warn(`[desktop-window] ${state.context} blank page detected, reloading once`, {
+        url: currentURL,
+        ...shape,
+      })
+      window.webContents.reloadIgnoringCache()
+    })
+  }, BLANK_PAGE_PROBE_DELAY_MS)
+}
+
 function escapeHtml(value: string): string {
   return value
     .replaceAll('&', '&amp;')
@@ -126,6 +205,9 @@ export function attachWindowDiagnostics(window: BrowserWindow, context: string):
   navigationStateRegistry.set(window, {
     readyForDetection: false,
     lastMainFrameError: null,
+    blankPageWatchdog: null,
+    blankPageRetried: false,
+    context,
   })
 
   window.webContents.on('did-start-loading', () => {
@@ -134,6 +216,7 @@ export function attachWindowDiagnostics(window: BrowserWindow, context: string):
       return
     }
     state.readyForDetection = false
+    clearBlankPageWatchdog(state)
   })
 
   window.webContents.on(
@@ -147,6 +230,7 @@ export function attachWindowDiagnostics(window: BrowserWindow, context: string):
       if (state) {
         state.readyForDetection = false
         state.lastMainFrameError = `${errorCode}:${errorDescription}`
+        clearBlankPageWatchdog(state)
       }
 
       console.warn(`[desktop-window] ${context} main-frame load failed`, {
@@ -167,6 +251,7 @@ export function attachWindowDiagnostics(window: BrowserWindow, context: string):
     state.readyForDetection = !currentURL.startsWith(errorPagePrefix)
     if (state.readyForDetection) {
       state.lastMainFrameError = null
+      scheduleBlankPageWatchdog(window, state)
     }
   })
 
@@ -174,10 +259,18 @@ export function attachWindowDiagnostics(window: BrowserWindow, context: string):
     const state = navigationStateRegistry.get(window)
     if (state) {
       state.readyForDetection = false
+      clearBlankPageWatchdog(state)
     }
 
     console.error(`[desktop-window] ${context} renderer gone`, details)
   })
+
+  window.once('closed', () => {
+    const state = navigationStateRegistry.get(window)
+    if (state) {
+      clearBlankPageWatchdog(state)
+    }
+  })
 }
 
 export function isWindowReadyForDetection(window: BrowserWindow): boolean {
@@ -193,6 +286,12 @@ export async function loadWindowURLSafely(
   targetURL: string,
   context: string,
 ): Promise<void> {
+  const state = navigationStateRegistry.get(window)
+  if (state) {
+    state.blankPageRetried = false
+    clearBlankPageWatchdog(state)
+  }
+
   try {
     await window.loadURL(targetURL, { userAgent: STANDARD_USER_AGENT })
   } catch (error) {