I lost my full profile (add-ons, bookmarks) when updating
I did the latest update of Firefox on 2019-06-04 and I got a strange message about safe mode. After ignoring this message (which was really not clear to me), I discovered that my entire Firefox profile was gone: all my bookmarks, add-ons and other preferences are gone.
Additional System Details
- User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:67.0) Gecko/20100101 Firefox/67.0
Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.