I'm not sure whether you mean the Primary Password that is used locally to encrypt the logins stored in the profile folder or about the password for the Sync account and have enabled 2FA (row-factor authentication) as only the latter requires access to an app to generate a six digit code. Can you clarify this ? In both case you will lose access, but with Sync this only happens if you want to restore data via Sync and do not have other devices connected. ---- *https://support.mozilla.org/en-US/kb/reset-your-primary-password-if-youve-forgotten-it *https://support.mozilla.org/en-US/kb/ive-lost-my-firefox-sync-account-information