GoKawiilApple warns thick webcam covers can crack MacBook screens, void warranty
Apple has cautioned that attaching a webcam cover to a MacBook can damage its display when the lid is closed, since the added thickness concentrates pressure on one spot instead of distributing it evenly. The company recommends covers no thicker than about 0.1mm, roughly the thickness of a sheet of paper, and notes that any resulting damage is not covered under warranty.