Uh-oh, I didn't bring a time machine. So first, if you didn't have a Master Password before, Firefox 76 asks you for your system login to view or copy the plain text of a password. More info in this article: [[Lockwise asks for authentication (password, voice, face or fingerprint) when accessing passwords]]. If you set a Master Password, then Firefox can ask for that instead. Setting a Master Password for the first time shouldn't erase any saved logins. If you '''reset an existing Master Password''', that certainly can cause data loss. More info on those issues: * [[Use a Master Password to protect stored logins and passwords]] * [[Reset your Master Password if you've forgotten it]] Now, if something happened that erased your saved logins, or the password portion of the logins, you may need to recover from a backup. Do you make any regular backups of your Firefox data, or have you recently used Firefox's Refresh feature? (On the date of the Refresh, Firefox would have moved your files to your desktop inside a folder named Old Firefox Data, so you could mine that folder for files.) If you don't have either of those, then we'll need to suggest some less common approaches.