I'm trying to recover a session, but it is not my last previous session (it's from a few sessions ago now I suppose). I started Firefox today and it didn't load the session from the previous night and instead loaded a couple of update pages that I closed. I then reopened Firefox realizing that it didn't reopen to my session and now restoring the previous session doesn't help because it opened to the updates (and I've now opened and closed it a few times trying to solve the issue). I've found a file in the session folder called "backup.session" that was modified last night and says it is a SESSION File, but can't seem to open it (web search for a program does no good and I don't see Firefox in the Browse for a Program section.

Is there anyway to open a session from a few sessions ago and is it through this backup.session file?