Ben Lovejoy, 9to5Mac:

A new web standard being recommended for adoption would open the way for both Face ID and Touch ID to be used to login to websites.

The API, known as WebAuthn, allows existing security devices – like fingerprint readers, cameras and USB keys – to be used for website authentication

And:

There’s as yet no word on Safari, but with all current and recent iPhones and iPads offering either Face ID or Touch ID, and the latter supported on the MacBook Pro too, this would be tailor-made for Apple. It cannot be used with other browsers without Apple’s support.

Very interesting.