Chosen Solution
You got a defective display! The artifacts you are seeing are scanning errors within the T-CON logic which is that small logic board that hands off of the display that sits inside the main body. You might find altering the screens settings might reduce the effect. BTW - Calibration is needed for the FaceTime camera and TrueTone services. I think you’ll find the camera is not working if this was a virgin unit, a used unit would have been calibrated and only Apple and its service centers have access to the needed tool.
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