[0.17.3] Train tracks appear over player/trees/vehicle when building

[Rotoscopic]

Was building some tracks while driving my tank around and the tracks overlapped my character+trees+vehicle, making it hard to determine precisely what direction the tank was pointed and what I was driving over (I was using it to clear trees at the time). I can't remember if this happened in previous versions, so seemed worth mentioning here.

https://imgur.com/RrjXYnq

[kovarex]

Yes, build preview is always on top as it needs to be visible.