The issue that I have is that I don't understand what is the problem that this extension is trying solve. In order for it to work at all, you have to have KeePassXC already open and accessing the database that you are interested in. Other than this, modern browsers already do autofill of names and passwords that you have supplied, the latter being transparently encrypted by the browser itself. I am sure that there are legitimate uses for KeePassXC-browser but, as far as I am concerned, it is far more trouble than it is worth.