It's only a deduction, Cit... I have no official info on it because we're not able to dissect it on our own in the new TE yet.
However, since I built the TA terrain, I know for a fact that the grass tile is one of my own custom tiles, devoid of any clutter. Since the grass tile in the TA is the only one that looks like it used to, that is my deduction.
I hope that can give Waffle somewhere to start looking...
