If i change the surface materials in the mesa_plateau_stone to be bedrock. i still get dirt and grass generated on the surface curve. This seems to be un-patched from the fix in 1.21.110.25 where the rest of the biomes have the the surface generation issue.
Reproduction steps:
Create a behavior pack that has a biome definition for mesa_plateau_stone with a different surface block.
Attach the behavior pack to the world
find a mesa_plateau_stone biome somewhere in the seed
Verify the biome is not changed to match the settings.
This appears to be a partial patch of the bug from 1.21.110.25. As it is a rarely generated biome it is easy to miss.
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Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response.
Could you please attach a proper behavior pack to the ticket?
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This bug ONLY exists in the the mesa biome as far as i can tell. i removed a bunch of the pack, but i am not going to do substantially more work to make this report happen. The bug repros with this pack in 1.21.120.26. if you cannot repro you need to ask clarifying questions. and again it is a biome specific bug