In-app browser: passkeys stored on a phone (cross-device / QR) never prompt #14398

Before submitting

• I searched existing issues and did not find a duplicate. [Bug]: In app browser not triggering passkey fingerprint to sign in on mac #5665 covers the Touch ID prompt for passkeys stored on the Mac. This issue covers passkeys stored on a phone, used cross-device over QR or Bluetooth.
• I included enough detail to reproduce or investigate the problem.

Area

Desktop preview browser (in-app browser)

Steps to reproduce

1. On macOS, open a site in the in-app browser whose account passkey is stored on a phone, not in the Mac's iCloud Keychain. I hit this on a Meta business login's "confirm it's you" passkey prompt.
2. Click "Use passkey".

Expected behavior

The same prompt Chrome and Safari show on the same Mac: a QR code or "use a phone or tablet", so the phone can approve the sign-in.

Actual behavior

The button spins indefinitely. No QR code or device picker appears, and no error is shown. In this case the site offers no other method from that prompt, so the user cannot sign in inside the in-app browser.

Workaround that worked: sign in with Chrome, then use Settings → Integrations → Browser profiles → Import from Chrome.

Impact

Blocks sign-in on sites that only offer a phone-stored passkey.

Version or commit

Desktop 0.0.44 (macOS)

Environment

macOS, desktop app connected to a remote Linux environment. The preview browser runs on the Mac.

Related

• [Bug]: In app browser not triggering passkey fingerprint to sign in on mac #5665: Touch ID prompt for passkeys stored on the Mac.
• fix(desktop): preview browser passkeys unlock with Touch ID on macOS #13857 and fix(desktop): support existing passkeys in the preview browser #13957: Touch ID and iCloud Keychain passkeys. As I read them, neither covers the cross-device (hybrid) transport.
• feat: expose WebAuthn hybrid transport via 'webauthn-hybrid-request' electron/electron#53733 (draft): exposes the WebAuthn hybrid transport via webauthn-hybrid-request. The preview browser would then need to show the QR / phone step.