Comment by nh2

Among

    Copyable vs Non-Copyable passkeys
    Transferable vs Non-Transferable passkeys
    Hardware-Backed vs Software-Backed passkeys
    User-Present vs Non-User-Present passkeys
    User-Verified vs Non-User-Verified passkeys
    Attested vs Non-Attested passkeys

They forgot

    Roaming vs Platform passkeys

(roughly: movable vs device-bound).

This is what e.g. PayPal uses to prevent you from using your Yubikey as a passkey, while it works perfectly as a passkey on other providers (e.g. Wise bank)

It's checkable in the browser with e.g.: `await PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable()`