I only discovered the tab groups function within the last few weeks, and upon finding, I moved dozens of open tabs into organized groups. On using the feature, I noticed the ability to save and close groups and that I could recover those closed groups by using the arrow in the browser toolbar. When I got to my PC this morning, my desktop had restarted or hibernated or something; when I started it up, Firefox was open which is unusual as I don't have Firefox set to open on startup - usually so I can restore sessions after crashes. All of my previously open tabs were open, but none of the closed, saved tab groups are visible. I cannot find any of the dozen or so closed tab groups and it appears I've lost easily hundreds of tabs. I tried looking at the session backups but it seems because Firefox was open on start, it overwrote the previous session data. Is there any way to recover those saved groups or am I SOL?