If it's just your bookmarks, see [[Recover lost or missing Bookmarks]] If all of your other profile data, such as passwords, add-ons and browser history is gone, you could try the suggestions posted in [/questions/1564691] starting with the following: 1. Enter ''about:profiles'' in the address bar and open all the listed profiles one by one (by clicking ''Launch profile in new browser''). Does one of them contain your data? If so, set it as your default profile. 2. If that's not the solution, see if you might have switched profiles in the new profile management system: (From [[Manage Firefox profiles#w_open-an-existing-profile]] '''Open an existing profile'''): #In the toolbar, click the account icon [[Image:IG profile]]. #Click the name of your current profile. #From the dropdown, just pick the profile you want to open. #;[[Image:Profile tab in account menu|width=400]]