Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The getPublicKey() method of the AuthenticatorAttestationResponse interface returns an ArrayBuffer containing the DER SubjectPublicKeyInfo of the new credential (see Subject Public Key Info), or null if this is not available.
This is a convenience function, created to allow easy access to the public key. This key will need to be stored in order to verify future authentication operations (i.e., using navigator.credentials.get()).