Failure is: ERROR TEST-UNEXPECTED-FAIL | chrome://mochitests/content/chrome/toolkit/components/passwordmgr/test/test_privbrowsing_perwindowpb.html | uncaught exception - TypeError: normalWindowIframe is null at chrome://mochitests/content/chrome/toolkit/components/passwordmgr/test/test_privbrowsing_perwindowpb.html:266