v136 · miscellaneous
Web Authentication Immediate UI mode
A new mode for navigator.credentials.get() that causes browser sign-in UI to be displayed to the user if there is a passkey or password for the site that is immediately known to the browser, or else rejects the promise with NotAllowedError if there is no such credential available. This allows the site to avoid showing a sign-in page if the browser can offer
concepts
-
Immediate UI
WebAuthn 'immediate' mediation surfaces the platform passkey picker without ambient page UI — closer to the OS-native flow.
-
No-passkey fallback
The full fork: immediate prompt OR password form. NotAllowedError is the signal to reveal the form — the reject path is what makes immediate safe on page load.
-
Mediation Matrix
Four conditions × four mediation modes in one truth table, with live buttons that fire a real
navigator.credentials.get()at the selected mediation and surface the resolve/reject signal. -
Error Decision Flow
Every reject path immediate mode can take (NotAllowedError, InvalidStateError, NotSupportedError, SecurityError, resolve) mapped to the correct fallback UI — with a live call to see which path your platform takes today.
why it shipped
Most sign-in experiences on the web are through sign-in pages that offer multiple options for accessing an account, such as username/password input fields, federated sign-in buttons, and sometimes explicit WebAuthn or passkey buttons. In cases where the browser is aware of passkeys or passwords that the user has for the site, this API feature would make the sign-in page unnecessary, by instead showing simple browser account selection UI when the user begins a sign-in attempt. Signing in with this flow would have less friction, and avoid user confusion from having to remember which sign-in opti