Hi LustStarrr, sorry to hear about your data loss. If you haven't already, could you close out of Firefox and do a normal Windows shutdown and restart to complete any pending updates and release any file locks. If Firefox again starts up without your data, could you check whether your stuff is available in a different ''profile'', as follows: '''Profile Manager Page''' Profiles are individual data folders. Firefox may have one or many. If a profile is locked, Firefox may create a new one. To view your profiles: In a new tab, type or paste '''about:profiles''' in the address bar and press Enter/Return to load it. Each listed profile has a name in large letters, and a little data table with some 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.''' Do you have another profile named '''default''' or default-''longnumber'' listed on this page? If so, you can check whether it is the one you were using more recently by clicking its '''Launch profile in new browser''' button. If it isn't what you want, simply close that new window. If it IS what you want, back on the about:profiles page, click the '''Set as default profile''' button for that profile so Firefox uses it automatically at the next startup. Any progress so far?