ITDominator

Easy Session Manager allows you to manage your Firefox session (tabs) by backing up or loading them in your current profile.

Alt Tab Page allows the user to select their preferred load page for new tabs and defaults to Google's when not in use.

This plugin can search, drag-n-drop ordering, and (un)hide all or some tabs. A search redirects automatically if the search is found and is a single instance. Search multiple windows by toggling the window icon on the bottom.

Better Youtube + works to improve the Youtube experience.