When I was quitting Firefox last time, Adobe flash tried to open a tab to download something, so I just forced quit. Now, I've just opened Firefox and it didn't restore my previous session as it usually does, and that option is not available in the History menu. I've looked in the profile folder in Finder but I don't think there are any .bak files from before I restarted it today. I had a lot of really important tabs in this session and I really need to get it back!