Firstly I do like the existing starfield glasses and please do not remove them, but unlike the starfield glass which only has one layer (like sky), Thaumcraft's magic mirror is rendering multiple "layers" (I assume) to create the depth effect via parallax as the camera moves. I uploaded a gif here to demonstrate what I mean more easily, you can see while moving left and right how the "stuff" in "real" magic mirror "moves at different rates" as if some of it is closer and some further away unlike the starfield glass which "remains stationary" at equal distance, so to speak:

Is there any chance this "multilayer magic mirror" is possible to add as another starfield glass type? Because it is an amazing visual and it would be nice for aesthetic uses in building. I understand it may be heavy on performance though.