If manifest URL has a different origin than a document, it must be ignored, see HTML5 paragraph 6.9.6 The application cache selection algorithm.
Created attachment 30276 [details] proposed patch Note that Firefox 3.1b3 fails this test - it creates an appcache, and even associates window.applicationCache with it, but then raises a security exception when trying to access the object.
Comment on attachment 30276 [details] proposed patch > +<p>Test that a different URL manifest is completely ignored.</p> You probably want the word "origin" here instead of URL. r=me
Committed revision 43631.