Fixed element collapsing in Safari

safari/ext/content.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2013 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 300 matching lines @@
 
     if (!safari.self.tab.canLoad(event, {
       type: "webRequest",
       payload: {
         url: event.url,
         type: type,
         documentUrl: document.location.href,
         isTopLevel: window == window.top
       }
     }))
+    {
       event.preventDefault();
+
+      // Safari doesn't dispatch an "error" event when preventing an element
+      // from loading by cancelling the "beforeload" event. So we have to
+      // dispatch it manually. Otherwise element collapsing wouldn't work.
+      var evt = document.createEvent("Event");
+      evt.initEvent(type == "sub_frame" ? "load" : "error");
+      event.target.dispatchEvent(evt);
+    }
   }, true);
 
 
   /* API */
 
   ext.backgroundPage = {
     sendMessage: function(message, responseCallback) {
       _sendMessage(
         message, responseCallback,
         safari.self.tab, safari.self,
         {
           documentUrl: document.location.href,
           isTopLevel: window == window.top
         }
       );
     },
     getWindow: function()
     {
       return proxy.getObject(0);
     }
   };
 
   ext.onMessage = new ContentMessageEventTarget();
 })();