Firefox may have a bug or corrupted files. I did update it recently when asked to do so No longer runs McAfee Web-Advisor ((McAfee could not fix it) and a game runs slow and hangs up or pauses for a couple minutes. Deep virus scan found nothing. McAfee and game run fine on Chrome (I don't like Chrome). Help please--what should I do? If uninstall and reinstall Firefox do I lose my bookmarks?