The Bug

Mineshafts generating in the badlands biome may generate a normal mineshaft instead of a badlands mineshaft, mainly from cave biomes generating under the surface. This causes fewer badlands mineshafts to generate.

How to Reproduce

1. use the seed -7985579858025862655
2. load up the world using default world type
3. teleport to -2490 -9 -2186
4. go up to the surface, notice its the badlands biome all around it

The Error

This mineshaft is not a badlands mineshaft, despite being in the middle of a badlands biome.