Loaded Firefox and it looked the same as always. Went to log into a particular site and the login info didn't pop up like it usually does. So I go to Options and Saved Logins... entirely blank. NONE. I had dozens in there! I close Firefox and reopen it. It comes up as Quantum. I did not ask for Quantum, I was not asked if I wanted to upgrade and I most definitely did NOT want all my logins and passwords deleted! Going to try finding the old logins.json file and see if I can restore the info. I'll update this if I am successful. However what I really want to know is how to prevent this from happening in the future. UPDATE: Found a logins.json.corrupt file, renaming it to logins.json restored all my saved info. So now my question isn't how to solve the problem, its how to prevent it from happening.