diff --git a/toolkit/content/tests/chrome/bug331215_window.xul b/toolkit/content/tests/chrome/bug331215_window.xul
index c074824fc2d..2028188b4c9 100644
--- a/toolkit/content/tests/chrome/bug331215_window.xul
+++ b/toolkit/content/tests/chrome/bug331215_window.xul
@@ -69,7 +69,11 @@
         gBrowser.addEventListener("pageshow", onPageShow, false);
         gBrowser.loadURI("data:text/plain,latest");
       }
-      setTimeout(_delayedOnLoad, 1000);
+      let tm = Cc["@mozilla.org/thread-manager;1"].
+               getService(Ci.nsIThreadManager);
+      tm.mainThread.dispatch({
+        run: function() _delayedOnLoad()
+      }, Ci.nsIThread.DISPATCH_NORMAL);
     }
 
     function onPageShow() {