Index: safari/ext/content.js
===================================================================
--- a/safari/ext/content.js
+++ b/safari/ext/content.js
@@ -58,11 +58,13 @@
 
   document.addEventListener("beforeload", function(event)
   {
+    var url = relativeToAbsoluteUrl(event.url);
+
     // 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))
+    if (!/^https?:/.test(url))
       return;
 
     var type;
@@ -95,7 +97,7 @@
     if (!safari.self.tab.canLoad(
       event, {
         category: "webRequest",
-        url: event.url,
+        url: url,
         type: type,
         pageId: documentInfo.pageId,
         frameId: documentInfo.frameId