Session Manager is a Firefox extension allowing you to save and restore your browsing sessions on the fly. It allows you to save the current state of Firefox (history, text data, the cookies and information entered in online forms ...etc) and reload these information later. Session Manager can also be configure to automatically backup your browsing session based on predefined parameters.
Open Firefox and go to this page: https://addons.mozilla.org/en-US/firefox/addon/session-manager/
To access the advanced settings of Session Manager:
To view your saved session:
Again, click the small arrow next to the save session button > Session Manager