Chroma Hills textures & using Nether portal in single player world causes a crash

Since the update, 1.12.13, going through a nether portal randomly crashes the game, approx 90% of the time, mostly when trying to go back to the overworld. This didn't happen before and at this point I avoid going to the nether.

edit: I discovered that the crashing seems to be related to using the Chroma Hills texture pack.