The window you are talking about has no slot for armor visible. It was designed to not be there but how they implemented it was to simply mask it away with an overlay. However the system still allowed you to drop something in the place but you couldn’t get it back out. The wight horse had a similar design cheat on it where you could add a saddle even though it didn’t have a visible slot to drop it. They patched that so the original and clear intent was now fool proof. What we were technically doing prior to that was exploiting flaws in the game.