Hi, it is because of security and passwords and this would be expected if someone wanted to look in your passwords. They can not. Security is only good if it works and it is working as intended. If it did not .....I would expect we would hear about it also.

Sorry you will loose your passwords. Your password that you make should be something that you can remember such as a short phrase.

Always make backups : it's a computer :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Please let us know if this solved your issue or if need further assistance.

As noted in the first reply, you can back up the locally stored data in the Profile folder of each installation of Firefox to avoid negative impact from having to start your Firefox Account (cloud data) from scratch.

Note: That's a different issue than the "Master Password" for one particular installation of Firefox. It's still a good idea to back up everything before using: Reset your Primary Password if you've forgotten it.

A Sync key derived from the password of the Sync account is used locally to encrypt all content before it is uploaded to the Sync server. Therefor if this password is changed it won't be possible to decode content on the Sync server and thus all this content is lost (invalidated). Also keep in mind that Sync isn't meant to be used as a backup and it isn't guaranteed that you can recover data that way. Best is probably to disconnect all devices if you do things that might lead to dataloss.