In the past, I've always relied on the 'Recently closed windows' option to retrieve my session when Firefox closes unexpectedly. However, lately, seemingly every time Firefox is closed out and then opened up again, 'Recently closed windows' is blanked out and the only option available is 'Restore previous session'--which, almost invariably, does not work and instead simply opens up a new instance of the homepage in a new window. Is there some way to disable the session restore functionality? Or to get 'Recently closed windows' to actually store my recently closed windows?