Restorning open tabs no longer occurs when re-opening Firefox
While the setting in Options, General is set to have Firefox restore the last set of open tabs and windows when Firefox re-opens, this no longer occurs. It previously occurred reliably and now this no longer happens post the latest update.
Wšykne wótegrona (2)
See item #31 for an explanation of what you need to have it the old way. Even if you do not act on choice given when you log out of Firefox, you can still use the History (:"Alt+H") menu to restore a previous session.
Make sure that you do not use "Clear Recent History" to clear the 'Browsing History' when you close Firefox.