I previously asked a question here https://support.mozilla.org/en-US/questions/977547#answer-502020 My problem was that every time I was closing firefox, i would lose all the tabs I had that I needed! it would restore the session before my prior session and not keep the ones i had. i'm not that tech savy so i tried looking online for a way to resolve it... i chose to follow one of the suggestions to delete all the "sessionstore.js" and "sessionstore.bak". I assumed they would refresh new in the folder. I reset firefox losing all my tabs trying to get them back again. sessionstore.bak came back but i do not have sessionstore.js i would really appreciate the help thanks!