Prevent Safari from freezing when loading large data: URLs

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 39 matching lines @@
       document.removeEventListener("visibilitychange", onVisibilitychange);
     };
     document.addEventListener("visibilitychange", onVisibilitychange);
   }
 
 
   /* Web requests */
 
   document.addEventListener("beforeload", function(event)
   {
+    // we don't block non-HTTP requests anyway, so we can bail out
+    // without asking the background page. This is even necessary
+    // because passing large data (like a photo encoded as data: URL)
+    // to the background page, freezes Safari.
+    if (!/^https?:/.test(event.url))
+      return;
+
     var type;
     switch(event.target.localName)
     {
       case "frame":
       case "iframe":
         type = "sub_frame";
         break;
       case "img":
         type = "image";
         break;
@@ skipping 330 matching lines @@
             messageProxy.handleResponse(event.message);
             break;
           case "proxyCallback":
             backgroundPageProxy.handleCallback(event.message);
             break;
         }
       }
     }
   });
 })();