Display the Google PageRank, Alexa rank and Compete ranking anywhere in your browser, along with fast keyword density analyser, keyword/nofollow highlighting, backward/related links, Alexa info and more.SessionManager
Session Manager saves and restores the state of all windows - either when you want it or automatically at startup and after crashes. Additionally it offers you to reopen (accidentally) closed windows and tabs. If you're afraid of losing data while...TabMixPlus
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.