Because someone at Cuppertino reactivated the Quicktime user-agent filter...
Created attachment 47690 [details] Fake QuickTime when accessing movie trailers
Comment on attachment 47690 [details] Fake QuickTime when accessing movie trailers User agent checking is bad behaviour.
Comment on attachment 47690 [details] Fake QuickTime when accessing movie trailers Clearing flags on attachment: 47690 Committed r54056: <http://trac.webkit.org/changeset/54056>
All reviewed patches have been landed. Closing bug.