Tools, Option GENERAL, "Show my windows and tabs from last time," and almost all of the time it doesn't, because?
Selected TOOLS, OPTIONS, GENERAL, "Show my windows and tabs from last time." Almost all of the time it doesn't restore those windows. User for years.
Wšykne wótegrona (2)
That sounds like it should work. Do you have Private Browsing turned on by any chance.
If the tabs aren't restored try the History menu for "Restore previous session" (though it would probably be grayed out for you as my guess).
check these out -- I will be mostly away for next 20 hours.
See item #31 Restoring tabs from a lost session
Also see Firefox does not ask to save tabs and windows on exit | Troubleshooting | Firefox Help
Wót David McRitchie
Make sure that you do not use Delete browsing, search and download history on Firefox to clear the 'Browsing History' when you close Firefox.