On the majority of modern videocards, it doesn't do anything. On a handful of videocards it does something odd like enable it when you try to disable and vice versa.
I first requested that someone fix it about four years ago, maybe more, and it was just ignored over and over. More recently, it was being discussed again and Skidracer said it wasn't possible. Someone offered a solution which he said worked across the board, and then there was no further word from BRL on whether that was, in fact, a valid solution or not.
In short, I wouldn't get your hopes up about it being fixed.
I first requested that someone fix it about four years ago, maybe more, and it was just ignored over and over. More recently, it was being discussed again and Skidracer said it wasn't possible. Someone offered a solution which he said worked across the board, and then there was no further word from BRL on whether that was, in fact, a valid solution or not.
In short, I wouldn't get your hopes up about it being fixed.