The plug-in working for me perfectly. all you need to do, is to enter the correct URL. Thank you!!

Works pretty good... on occasion you may have a funky website that you may have to hunt down a reliable login address for... for what it is it works great with a minimal amount of fuss.

The extension has a beautiful interface - unfortunately, unlike KeePass, KeePassXC cannot communicate with a personal server. This is not the fault of the developer, but he just went with KeePassXC instead of Keepass - I can't give five stars because the overall concept is not perfect for me. Oh well... I give 4.5.

I've been using this plugin with both KeePassXC and KeePass (via a fork of the natmsg agent) and it works great. Occasionally loses connectivity, but that's usually only after I've had the program up for weeks and due to high load on my workstation which causes. If that happens to you just restart the natmsg processes and all is well again!

Was a little bit difficult to understand how to use it for Mozilla account:
Find it in https://support.mozilla.org/en-US/questions/1276862:
Create a Keepass entry for Firefox and highlight it in the list
From the menu bar select [Entries->TOTP->Set up TOTP...]
Display the QR code in the FF set up web page and copy to the [Secret Key:] field from above.
Accept defaults and press [OK]
From the menu bar select [Entries->TOTP->Show TOTP..].
copy this number into the response field in the FF set up web page

It should now be all set up.
To use highlight the entry and select [Entries->TOTP->Show TOTP... ](or copy TOTP... if easier)