Ever since the launch of WebM, the open source web video format, YouTube has been encoding videos uploaded at 720p or higher resolution in the WebM format. There are lots of videos on YouTube which are available in WebM format. You can search WebM videos in YouTube using a custom search query and for this query, you can create shortcuts on Firefox, Google Chrome and Opera. You can find these instruction to search WebM videos here.
To find out if any YouTube video is available in WebM, simply add &html5=True (make sure True is capitalized) to the end of the video URL. If there is a WebM version of the video, it will open instead of the Flash version. For example:
- Flash version: http://www.youtube.com/watch?v=Dz6gFokvOr0
- WebM version: http://www.youtube.com/watch?v=Dz6gFokvOr0&html5=True
If you can’t find WebM videos it is most likely a browser cookie problem. You need to first enrol to YouTube’s HTML 5 beta test (it can be done here: http://youtube.com/html5). Your enrolment in the YouTube HTML5 beta test is stored in a browser cookie (not in your YouTube or Google account), and that cookie can expire. Re-set the cookie to view videos in WebM format.