Firefox (FF) 103.x has been set in Settings NOT to restore automatically the previous session-- ie. the check-box in Settings for startup is empty/clear. Yet, FF autoloads the previous session, anyway, after about 45 to 60 seconds. Put another way, FF does not follow my instructions for the item left clear in Settings. In the typical FF startup, immediately after loading FF, the screen is empty of tabs provided by the application I normally use, named Tree Style Tabs. The screen should stay that way until I decide to load the previous session. On checking the FF top menu, I find Restore Previous Session is in BOLD, which means the previous session can be restored at my discretion. That is the way I prefer FF to operate. Yet, 45-60 seconds later after FF startup, the FF screen flashes, and the previous session loads. When I check the top menu, the Load Previous Session item is no longer in boldface type. As a test, I cleared the stack of tabs by closing each tab except one, and restarted FF. As usual, the single tab auto-loaded 45-60 seconds after starting FF. Under Settings, the Load Previous Session item was no longer in boldface type (since it had loaded, already).