Tags that contain other video formats are not touched.
"The Add-on replaces video tags only if the video formats specified in the tag are among those supported by Windows Media Player. "The Extension is based on a Firefox Add-on that parses HTML5 pages and replaces Video tags with a call to the Windows Media Player plug-in so that the content can be played in the browser," according to the release notes. Most Firefox users are probably using Microsoft's latest and greatest, but a large portion are either using Mac, Linux, or an older version of Windows. Not only will they need to download the plug-in, they will need to be running Windows 7. It's still not a full-proof solution for Firefox users. A: Launch up Internet Explorer>Tools> Manager Add-on. Step3: Remove OpenH264 Video Codec from Your Browser. Since Windows 7 has built-in support for playing H.264 content, Microsoft's solution is to let Firefox tap into that capability. Click Start> Control Panel> Programs and Features> search for OpenH264 Video Codec or suspect applications> right click and choose Uninstall. The code is also too expensive the H.264 patent license agreement isn't cheap, and is also extremely limited in what it allows. The Mozilla Foundation refuses to provide support for H.264 in Firefox because it's against their open nature. At the same time, Microsoft is still pushing H.264 support and its first target is Mozilla. Although Internet Explorer 9 supports H.264, excluding all other codecs, Microsoft says it is making an exception for WebM, as long as the user installs the corresponding codec. Here's the current state of HTML5 video: Microsoft and Apple are betting on H.264, Firefox and Opera are rooting for WebM, and Chrome does both.
Even though Firefox is a big competitor to Microsoft's own Internet Explorer, the software giant has decided it's for the best if Firefox can play back H.264. The HTML5 Extension for Windows Media Player Firefox Plug-in is free to download but it's release is quite controversial.
Microsoft has updated its Windows Media Player plug-in for Mozilla Firefox so as to enable H.264-encoded video on HTML5 by using built-in capabilities available on Windows 7.