Crashed Firefox Port App

My old version of Firefox Portable App crashed; it asked to send a 'crush report' but the bottoms don't have characters below it; the crush message that comes up when I run the *.Exe file it said that if win try to restart and load my open tabs but, Nothing happened.
How can I get my Tabs Session back? I would like to update to the latest portable Firefox release but, I am afraid by doing so, I may override the possibility of getting my opened tabs from the previous time Firefox portable worked before, given me this error.
Thanks for any advice.