Add WebAuthn / FIDO2 as 2FA/MFA

It would be helpful to have WebAuthn / FIDO2 as two-factor authentication (2FA) supported.

For U2F there is a similar request, but FIDO2 / WebAuthn is its successor.

WebAuthn would allow you to use a USB/NFC security key to perform a second factor authentication just by pushing a button, without that you have to deal with authenticator apps on your phone by manually entering time based one time passwords (TOTP).