Get Firefox to support H.264

The FFmpeg plugin for GStreamer 0.10 is not available in the official Ubuntu 14.04 repositories (because FFMpeg is not available either - libav is used instead) and because of this, Firefox doesn't support the H.264 codec.

Furthermore, without the FFmpeg plugin for GStreamer 0.10 package, KDE apps can't play H.264 videos in Kubuntu 14.04 if they use the GStreamer backend. Another issue with this is that Amarok can't play WMA files. There might also be other affected applications.

To "fix" this, all you need is install the "gstreamer0.10-ffmpeg" package and its dependencies. If you've upgraded from an older Ubuntu version, this package might already be installed but if this is a fresh install, you can get the package from a PPA. Add the PPA and install it using the following commands: