diff --git a/dom/tests/mochitest/whatwg/postMessage_chrome_helper.html b/dom/tests/mochitest/whatwg/postMessage_chrome_helper.html
index a93cc5b46b89..86a57ed0f6af 100644
--- a/dom/tests/mochitest/whatwg/postMessage_chrome_helper.html
+++ b/dom/tests/mochitest/whatwg/postMessage_chrome_helper.html
@@ -37,9 +37,7 @@
     
     function respond(msg)
     {
-      // ...so get privileges and test that this works with privileges
-      netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
-      window.parent.postMessage(msg, "*");
+      SpecialPowers.wrap(window).parent.postMessage(msg, "*");
     }
     
     window.addEventListener("message", receiveMessage, false);
diff --git a/dom/tests/mochitest/whatwg/test_postMessage_chrome.html b/dom/tests/mochitest/whatwg/test_postMessage_chrome.html
index 2ba2a6622883..e50ef6f0947f 100644
--- a/dom/tests/mochitest/whatwg/test_postMessage_chrome.html
+++ b/dom/tests/mochitest/whatwg/test_postMessage_chrome.html
@@ -93,10 +93,6 @@ function chromePathIsSet(evt)
 function receiveContent(evt)
 {
   is(evt.isTrusted, true, "should have sent a trusted event");
-  is(evt.origin, "http://example.org", "content response event has wrong URI");
-  is(evt.source, window.frames.contentDomain,
-     "wrong source for same-domain message!");
-
   finish();
 }