Floating copper grates in trial chamber room

In the trial chambers there should be no floating elements: all platforms, beams and spaces are suspended by chains, the wall, the floor, or the ceiling. However in the trial room that has four or five floors in a narrow vertical space, looking a bit like a zigzag when viewed from the side, has some floating copper grates at the very top of the room. This probably isn’t a bug and was just a mistake on the designers’s parts. I have attached photos of the room and the specific floating element in question.

You can notice this problem yourself by heading to the top of one of these rooms.