Sadly it does not work with some major authenticators (eg microsoft).
When it works it's nice - tried it with Octa.
When it does not work it's very confusing, as it won't give you an indication of what's happening. The interface is very basic, can't really tell what's what, how to start. Weird icons instead of simple textual buttons is a rubbish modern fad.

Completely broken and useless. No icon appears in the navigation bar.

This add-on has been a godsend for me setting up 2FA on various sites. Unfortunately as of today the "Scan QR Code" button is doing nothing, and I can't add additional sites to the authenticator app. Not sure why this is failing at the moment. It would be great if the developer could look at this issue.

I'm so glad that I downloaded this extension. I use it constantly and it saves me a TON of time. Now I use 2FA for every single account and don't have to find my phone every single time. VERY HIGHLY RECOMMEND.

Good. No issue at all.

i have no idea how to use this app, how to open, how to add an account, on a PC

This extension is great!

dont work on my firefox (plugin not appear in toolbar) :-(