I have my Yoti ID fully setup on my phone and I'm glad to see the password vault feature integrated into major browsers.
I'm not using Yoti as a primary password manager, rather just storing very difficult passwords for my main vault (KeePass) as the Android app lacks of hardware key support what I'm using in Windows.
The add-on works well, however the icon next to the identified fields such as username and password overlaps the icon what's already there making the other icon pretty much unusable. As I said before, I use Yoti to store passwords for other databases, and their add-on works in a similar way, it places an icon next to the login fields. That icon would give a list of records that belong to that place (website) but having the Yoti icon covering it, the icon is unreachable. This is one of the issues.
The other one is more annoying. Accessing some more complex websites like Coinbase Pro needs more resources and although I have a quite strong computer, Firefox often notifies me with yellow background about the Yoti add-on that slows the page down. It quickly disappears but sometimes it comes up multiple times within a minute.