How do you make invisible bricks?

[Wingy]

aquaMat wrote: I'm not even sure if I remember the correct order of proceedings, as I worked pretty long on that...trying out different things until it really worked..... but I achieved the effect by first adding bricks in a layer other than layer 4 and later removing them again. The setting of the

fringe

is essential.

Did you remove some of the fringe from layer 3 or something to get rid of the generated fringe or something by using the black nothing-ness tile on the fringe? Was that a part of the process?