Actually just started some work on some biometric FIDO2 webapp testing, and there are frustratingly few device options available to use for testing, particularly in linux. It works fine on most modern mobile devices, but I need to get into the guts of things, so I need an actual FIDO2 biometric device so it has been a little frustrating. - I don't suppose anyone knows of any device emulators/simulators our there, to test a webapp?
The fingerprint reader on my Thinkpad X1 Carbon (gen 7) can work as a FIDO device. I just re-tested it on https://webauthn.io/ with Firefox in Windows 10. I'm guessing other fingerprint readers will too. You need to know that it will be considered a "Platform" device rather than a "Cross platform" device, which is what YubiKeys are considered.
Related but not answering your question: I haven't found any major website that support Platform FIDO devices. I'm guessing they only want 2FA devices which can roam between computers. I think that's unfortunate. Perhaps a good policy would be to allow Platform devices to be used after a Cross Platform device has been registered first. But there are few websites that support multiple FIDO keys to begin with.
How nice would it be to log into websites with your builtin fingerprint reader? The client side stuff seems ready to go.
