fix: better window hierarchy checks

lib/browser/guest-window-manager.js

@@ -1,6 +1,7 @@
 'use strict'
 
 const electron = require('electron')
+const nodeUrl = require('url')
 const { BrowserWindow } = electron
 const { isSameOrigin } = process.electronBinding('v8_util')
 const { ipcMainInternal } = require('@electron/internal/browser/ipc-main-internal')
@@ -177,9 +178,8 @@ const isNodeIntegrationEnabled = function (sender) {
 
 // Checks whether |sender| can access the |target|:
 const canAccessWindow = function (sender, target) {
-  return isChildWindow(sender, target) ||
-         isScriptableWindow(sender, target) ||
-         isNodeIntegrationEnabled(sender)
+  return isScriptableWindow(sender, target) ||
+         (isChildWindow(sender, target) && isNodeIntegrationEnabled(sender))
 }
 
 // Routed window.open messages with raw options
@@ -187,6 +187,12 @@ ipcMainInternal.on('ELECTRON_GUEST_WINDOW_MANAGER_WINDOW_OPEN', (event, url, fra
   if (url == null || url === '') url = 'about:blank'
   if (frameName == null) frameName = ''
   if (features == null) features = ''
+  const parsedSourceURL = nodeUrl.parse(event.sender.getURL())
+  const parsedTargetURL = nodeUrl.parse(url)
+  if (parsedTargetURL.protocol === 'file:' && parsedSourceURL.protocol !== 'file:') {
+    event.returnValue = null
+    return
+  }
 
   const options = {}