Firefox 26 and H.264 on Ubuntu

[Jim Byrnes]

Running Ubuntu 12.04.

Firefox just updated to 26. Looking at changes here [1] it says there is 
support for H.264 on Linux if appropriate gstreamer plug-ins are installed.

I went a Html5 test page [2] and it says I got 426 out of possible 555 
points.  In the upper video section I had support for only 2 out of 7 
categories, video element and Poster image.  In the lower section it 
says I have H.264 support but not MPEG-4 support.

So what are the appropriate gstreamer plugins they mention?  Are they 
installed by default on 12.04.  I couldn't find a list anywhere.  Using 
synaptic I see some are installed and others are not.



[1] http://www.mozilla.org/en-US/firefox/26.0/releasenotes/
[2] http://html5test.com/

Thanks,  Jim