YouTube High Definition is a powerful tool that will let you automatically play all YouTube videos in HD (High Definition), turn off annotations, change video player size, auto stop videos, auto mute videos, control embedded videos and much more.
Tab Mix Plus enhances Firefox's tab browsing capabilities. It includes such features as duplicating tabs, controlling tab focus, tab clicking options, undo closed tabs and windows, plus much more. It also includes a full-featured session manager.
Collections are groups of related add-ons that anyone can create and share.Explore Collections