chromium/chrome/test/data/webauthn_conditional_mediation.html

<html>
<head>WebAuthn Conditional UI test page</head>
<body>
  <form action="" id="testform">
    <input type="text" autocomplete="username webauthn" id="username" name="username">
    <input type="password" autocomplete="current-password webauthn" id="password" name="password">
    <input type="submit">
  </form>
</body>
</html>