I lost all my tabs groups with the the update to release date for Firefox 138.0.4 on the 2025-05-19. Tab groups are still configured but my sessionstore.js is missing. I notice that there is a backup in Session-store backups dated the 2025-05-19 so I presume the tabs groups are still stored there. Can anybody suggest how to get the tab functionality back? I'm hesitant to just restore the sessionstore.js -- the actual tab group functionality is gone. I can't even recreate the groups.