A local preflight for passkey users

Find the overlap before your passkey is the only way in.

See whether password-manager extensions may compete for the same passkey request, check browser capability, and leave with a recovery-first plan.

Download for Chromium Install instructions

Free and inspectable. No account, credential access, analytics, or network requests.

A paper-cut scene of overlapping browser windows, provider cards, a passkey, and an inspection lamp
Overlapping provider layers, made visible before sign-in.

ChecksProvider coexistence

TestsNon-secret WebAuthn capability

CreatesA local recovery checklist

Never readsPasswords, passkeys, or pages

Why preflight matters

Two helpful extensions can become one invisible conflict.

Passkey providers can respond to the same browser ceremony. When more than one is enabled, a known coexistence defect can suppress or derail the prompt—and the worst time to discover it is after removing your fallback.

This check inventories known providers where the browser allows it, lets you fill in what it cannot see, and clearly labels uncertainty. It does not simulate a real account login.

Three local steps

An inspection sheet, not a security score.

  1. 01

    Inventory providers

    Grant optional access to extension names and enabled state, or confirm providers manually.

  2. 02

    Check capability

    Ask the documented WebAuthn API whether a built-in authenticator is available. No sign-in begins.

  3. 03

    Prepare recovery

    Resolve overlaps, keep a session open, and export a plain-text checklist before changing login methods.

Specific, explainable findings

Know what needs attention—and what the browser cannot prove.

Every result includes a reason and a next action. “Unknown” stays unknown; it is never colored green.

Private by construction

Your extension list does not become our data.

Install the v1 package

Run the check before your next passkey change.

The downloadable package is an unpacked-development build for Chromium browsers. Store review and Firefox packaging are planned next.

  1. Download and unzip the package.
  2. Open chrome://extensions and enable Developer mode.
  3. Choose “Load unpacked,” select the folder, then click the toolbar icon.
Download extension