I have about two hundred tabs still using the tabgroups extension. I made the dreaded mistake a couple of days ago: a site opened a new window (not tab), and while exiting firefox, i first closed the window with the cca 200 tabs, and only then the window with only one tab. Upon restart, only the one tab was restored. Important info pehaps: I am also using tabmix plus, and I am not 100% sure right now if i'm using their session restore or the FF builtin session restore. Is there a place where some history of my tabs is kept so i can somehow use it to restore my 200 tabs? :( Many thanks in advance for any pointers!