Re-load tabs
Even though I have settings set to load previous tabs when Firefox is started up but when it is restarted it doesn't load the tabs. This has only occurred the last few days. My solution is to select "reopen all windows" which does what I want but also opens several other versions of Firefox. Noteworthy, confusing, but probably not associated: In the course of trying to work through this, I have had a baseball playing on Chrome. I ended up closing out Chrome but the baseball game audio continues even though the Chrome appears to be closed on the taskbar.
Opaite Mbohovái (1)
It sounds like you might have multiple windows of Firefox open at the time you're closing out Firefox. When you close out of Firefox are you closing each window with the "X" in the top-right corner? I believe Firefox will only restore the absolute last window you had open when you open it next time.
To try diagnosing if that's what's happening, next time you close out of Firefox, try closing the application with the Exit feature instead. You can find this at the bottom of the application menu (the one that looks like three horizontal lines). Alternatively you can use the keyboard shortcut Ctrl+Shift+Q.
This will close all windows simultaneously and should restore them again when you start the program again.
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