fix: ensure guest-embedder map is updated when webview is removed

lib/browser/guest-view-manager.js

@@ -251,6 +251,9 @@ const attachGuest = function (event, embedderFrameId, elementInstanceId, guestIn
 // Remove an guest-embedder relationship.
 const detachGuest = function (embedder, guestInstanceId) {
   const guestInstance = guestInstances[guestInstanceId];
+
+  if (!guestInstance) return;
+
   if (embedder !== guestInstance.embedder) {
     return;
   }
@@ -341,6 +344,10 @@ handleMessage('ELECTRON_GUEST_VIEW_MANAGER_ATTACH_GUEST', function (event, embed
   }
 });
 
+handleMessageSync('ELECTRON_GUEST_VIEW_MANAGER_DETACH_GUEST', function (event, guestInstanceId) {
+  return detachGuest(event.sender, guestInstanceId);
+});
+
 // this message is sent by the actual <webview>
 ipcMainInternal.on('ELECTRON_GUEST_VIEW_MANAGER_FOCUS_CHANGE', function (event, focus, guestInstanceId) {
   const guest = getGuest(guestInstanceId);

lib/renderer/web-view/guest-view-internal.ts

@@ -1,5 +1,6 @@
 import { webFrame, IpcMessageEvent } from 'electron';
 import { ipcRendererInternal } from '@electron/internal/renderer/ipc-renderer-internal';
+import * as ipcRendererUtils from '@electron/internal/renderer/ipc-renderer-internal-utils';
 
 import { WebViewImpl } from '@electron/internal/renderer/web-view/web-view-impl';
 
@@ -105,8 +106,13 @@ export function attachGuest (
   ipcRendererInternal.invoke('ELECTRON_GUEST_VIEW_MANAGER_ATTACH_GUEST', embedderFrameId, elementInstanceId, guestInstanceId, params);
 }
 
+export function detachGuest (guestInstanceId: number) {
+  return ipcRendererUtils.invokeSync('ELECTRON_GUEST_VIEW_MANAGER_DETACH_GUEST', guestInstanceId);
+}
+
 export const guestViewInternalModule = {
   deregisterEvents,
   createGuest,
-  attachGuest
+  attachGuest,
+  detachGuest
 };

lib/renderer/web-view/web-view-element.ts

@@ -66,6 +66,9 @@ const defineWebViewElement = (v8Util: NodeJS.V8UtilBinding, webViewImpl: typeof
         return;
       }
       guestViewInternal.deregisterEvents(internal.viewInstanceId);
+      if (internal.guestInstanceId) {
+        guestViewInternal.detachGuest(internal.guestInstanceId);
+      }
       internal.elementAttached = false;
       this.internalInstanceId = 0;
       internal.reset();