Maybe a bug, maybe not. Not new to 1.13. Seed: 7913388302499728605 - coordinates: 875 88 8474. Note that this cliff is aligned to the middle of the chunk.
Second example: Seed: -5141882208578940786 252 70 152.
MC-125034
Weird little cliffs at quarter chunk borders
Resolved
Won't Fix
4
(Unassigned)
Confirmed
World generation
world-generation
Minecraft 1.12.2, Minecraft 18w06a, Minecraft 18w08b, 21w16a, 21w18a
Retrieved
Can confirm in 21w18a. It has the 4x4 pattern from MC-125052, so it's possible they're caused by the same thing.
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