I lost a session with many tabs. Unfortunately "Restore previous session" was not available. I found a upgrade.jsonlz4 file with a date and time which would have the tabs on it. The size is larger than other ones so I figured this was the best option. I coppied this and pasted it into profiles. Renamed it sessionstore.jsonlz4... Renamed the sessionstore that was in there already to sessionstoreOLD Restarted firefox and when I click on restore previous session button I just get 2 blank tabs. I then tried the other files which are significantly smaller but still no dice. I tried the jefferson scrounger and it just gets stuck on "processing" Any help would be much appreciated. Please see screenshot of the files I had available to me and saved to a usb.