the autofiller from firefox fills in the password in the android and desktop version when you want (or someone else wants to change respectively see) wants to change the password for firefox sync (in settings sync). the password access per fingerprint makes no sense this way.
Also the masterpassword feature makes no sense this way (besides that you can just cancel or check the cross to access all the prefilled passwords of shopping and so one websites).
maybe only few people would always delete this password in the pw manager from firefox again and again.
