hello, have you switched between firefox 31 and a higher version in august once - there has been a change in the database that holds your passwords and the migration will only take place once - the first time you update from firefox 31 to a higher version. if you switch back to 31 again afterwards (downgrading isn't a path that is commonly supported) your pw changes won't be reflected...

Yes, I tried nightly around that time for a few days. And then switched back to stable version which uses old database system, as I now see. The thing is I changed a lot of passwords in august. What can I do to convert old database to the new format again? Thanks.

i'd suggest creating a backup of the contents of your current profile first before you proceed: Back up and restore information in Firefox profiles

you can try to enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named signon.importedFromSqlite - right-click and reset that entry to the default value and restart the browser afterwards, this might get rid of any password changes you have done in nightly though.

Unfortunately, it didn't help. The value just changes to true after the restart and I keep seeing old passwords from the first migration. Maybe there's another way to fool firefox into thinking this is a first start on a new database? Thanks.

you might have to go into your profile folder and delete the logins.json file (make a backup first!) in there manually and attempt the procedure again...

Thank you very much, that helped.