I've had the extension for some time now and just getting around to really playing with it. Seems to work very well for some of its features but for others I can't seem to get them to work, meaning if for example there is a keyboard shortcut to have YouTube do XYZ when I use that shortcut nothing happens. This is not for just one feature either nor is it a dead key on my keyboard. Another weird thing is it will often just "turn itself off" meaning out of no where and for no reason I can find the control bar will just disappear from Firefox around the YouTube player window. Then I will have to click around turning it on and off, enabling and disabling the extension even uninstalling it then reinstalling it (having the export of the settings as a backup makes this a lot less annoying after the first couple of times once I realized there was a backup and doing that would make this troubleshooting step hell of a lot less annoying.) Anyways - overall it has some awesome settings and features especially the quick list of shortcuts which makes life so much easier.