Building last WebKit trunk and trying to load html5test.com with the minibrowser causes this: - Apple port: The spinning wheel appears, but it shows nothing more than that. It keeps stuck on the spinning wheel. - GTK port: a JS error is thrown: Test has failed: undefined is not an object (evaluating 'MediaSource.isTypeSupported') and after that an about page of the test appears instead of the results.
In the case of GTK+ this fixes the issue: Tools/Scripts/run-minibrowser --gtk --release --enable-mediasource=true http://html5test.com/ That is: enabling the runtime flag media-source before loading the page.