I have seem similar things … but it seems like there are at least 2 different issues
- (A) a “correct” mountain getting progressively refined in a way that feels visually disturbing
- (B) a flat region getting rendered as a “mountain” from a distance … and when you get closer they disappear.
Here is one example (pre 1.12.13.0) where I was flying back home to Hilo (Hawaii) … and almost on the beach, right ahead of me I can see three gigantic triangles (hills?) … but that area is (and later turns) flat.
Update: I found that the following discussion is more related to the bug I have seen on Hawaii: