Install H.264 support

~~The FFmpeg plugin for GStreamer 0.10 is not available in the official Ubuntu 14.04 repositories and because of this, Firefox doesn’t support the H.264 codec.~~

~~all you have to do is install gstreamer0.10-ffmpeg by using a PPA:~~

sudo add-apt-repository ppa:mc3man/trusty-media sudo apt-get update sudo apt-get install gstreamer0.10-ffmpeg

Update august 2016:

This PPA seems offline.

This website gives an apt-URL to install the needed codes bij one click each:

For H.264 support install this codec:

http://www.ubuntuupdates.org/package/core/xenial/universe/base/x264

For H.256 support install this codec:

http://www.ubuntuupdates.org/package/core/xenial/universe/base/x265