- Invite opens an appearance-matched poster with the app icon, inviter name,
QR code, and short code; tap for a full-brightness QR view; save (add-only
Photos access), share, or copy the link. Mac shows the poster in a popover
and can save it as PNG.
- Accounts get look-alike-free 8-character codes. "I have a code" accepts a
code, link, or pasted message during the server-defined binding window.
- Permanently rejected redemptions show a specific message and drop the
stored code instead of retrying on every sign-in.