https://wccftech.com/iphone-13-face-id-disables-with-non-genuine-display/

Apple has introduced additional unauthorized third-party repair lockdown measures with the release of the iPhone 13. If a customer decides to replace the display with a non-genuine part, Face ID will stop working for them, as shown in this latest repair video.

As shown by Phone Repair Guru’s YouTube channel link below, the iPhone 13 screen does not feature any attached Face ID components and can be replaced separately. Unfortunately, if you are not licensed with Apple through its Independent Repair Program, you will receive a warning label on the iPhone’s home screen that the display is non-genuine, and once you hop in the Face ID menu, it will refuse to work.