I recently ran into the problem on one of my Linux installations where I could not watch !YouTube videos from Firefox. I have all the plugins, but some sort of error occurs and the video won't play. As a workaround, I found out that I could use Totem to browse and view !YouTube.

• Start Totem viaApplications > Sound & Video > Movie Player
• Click onEdit > Plugins
• Make sure you place a check in the box labeledYouTube browser
• Click Close to save changes

Select !YouTube from the box located in upper right side of Totem. Type a search such as “Dane Cook” and hit the [Enter] key. Totem will search !YouTube.com for your keywords. It will load results in sidebar. Simply double-click a video to watch it.

Before the !YouTube plugin will work with Totem, you will need to install gst-plugins-bad.

sudo apt-get install gstreamer0.10-plugins-bad

– Main.FredPettis - 12 May 2009