Visual rendering error: When you cover a slope with paving stones and then cover it with soil, a bug appears in the image.
V0.8.6C

Visual rendering error: When you cover a slope with paving stones and then cover it with soil, a bug appears in the image.
V0.8.6C

I have noticed myself that surfaces can sometimes get stuck when terrain is modified over/under them; they don't always break like they're supposed to, particularly in terrain collapses caused by deep-sea dumping (when the surface in question goes right up to the edge). My solution is to always remove surfaces before terraforming near them, but that's a workaround more than anything else.
That said, I haven't tested lately, and you haven't mentioned a version?
Hmm... I did more testing. It looks like the tiles will hold up even though I dumped dirt on them.