Read by Council Buildhelper: Temporary Blocks instead of single lines

[Purplehain]

as my header suggest, i would replace the single lines that are drawn every frame with temporary blocks with an invisible texture. that would get rid of the lags you get with an big sized build helper imho, and would give the possibility of filling those boxes in mid air

 

[Keptick]

Have you ever tried pasting a large object? It will display a preview (if you have the setting on) made out of transparent blocks (like you're suggesting).

It can and will drop your FPS to less than 1. It's WAY worse than just having the wire outline.