Hi, I see your thread from a couple weeks ago here: https://support.mozilla.org/questions/1419059 For background, your Firefox data like bookmarks are stored in a profile folder. You can have multiple profile folders, so one possible reason for starting up and getting nothing familiar is if Firefox created a new profile folder instead of using your regular one. It sounds like right now, everything is fine. In preparation for the update, could you make a note or grab a screenshot of information about your profile? Here's where you can find it: '''Profile Manager Page''' Inside Firefox, type or paste '''about:profiles''' in the address bar and press Enter to load it. This page should list at least one profile and could list many. (Each profile has two folders and one or more buttons. Do not use any Remove buttons!) The profile that Firefox is currently using will have this: '''This is the profile in use and it cannot be deleted.''' Please make a note of the profile name above that message, and the "Root Directory" listed below that message. If something goes wrong down the road, then you'll know which is your regular profile that you need the updated Firefox to use. One way to save this information is to email it to yourself, but if you have a way you prefer to keep notes, that would be fine, too. Can you follow me on this so far? P.S. This site doesn't accept email replies, so please follow up here at https://support.mozilla.org/questions/1420504