Do you have Firefox as your web browser and do you use Avast Antivirus? You might have problems with lost passwords in Mozilla Firefox.
Users report that the combination of Avast Antivirus and Mozilla Firefox can cause Firefox to lose all stored passwords because Avast Antivirus can cause an important file that stores login data in Firefox to become corrupted.
Avast Antivirus detects the file: login.json and places .corrupt after it, the file name becomes login.json.corrupt.
This corrupt file prevents Firefox from using the login.json file and therefore from using the stored saved passwords. There is a simple solution that the user can do to recover the passwords in Firefox.
Mozilla has introduced a fix to restore the passwords file from Firefox. Just install the browser extension add-on and Firefox will restore the affected login file.
Both Mozilla and Avast are aware of the issue and have released a fix.
Make sure to update Avast Antivirus and Firefox to the latest version.