This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
See the test at http://w3c-test.org/html/tests/submission/Opera/media/interfaces/TextTrack/activeCues.html. It contains the following code to determine the <video> src to be used on line 101: video.src = '../../resources/media/sunflower.' + (video.canPlayType('video/webm') ? 'webm' : 'mp4'); This isn't a very robust approach as .canPlayType('video/webm') returns "maybe" on a WebKit nightly when webm is not actually supported, but the string "maybe" evaluates to "true" as a JS condition, and thus the WebM file is used. The test should be rewritten such that it either: 1. uses <source> elements to let the browser pick the suitable resource 2. checks that .canPlayType() returns "probably" to assume that the tested type can be played.