Once I’ve installed InvisibleShield Glass Curve, why is there a clear border or halo around the perimeter?

The clear border around the perimeter of the Glass Curve is the adhesive that secures it to your phone. The best way to ensure glass screen protection remains bubble-free on a curved screen phone is to use adhesive only around the border of the phone. By running the adhesive around the entire perimeter, we ensure that dust particles and lint can’t get underneath the screen protection.