Can't change curtain wall glass elevation color

[wilderrasp]

First choice would be to have the shower door installer install a glass panel on top of the knee wall. They typically have a trim piece to mount the panel to the tile, and then caulk it in with silicone. Keep in mind that the panel would most likely be custom work and cost more. Anchoring the panel to the ceiling adds rigidity, and the metal edge will act as the door stop (unless double acting).