I made a datapack that adds new cave biomes with mineshafts and strong holds but only generates in multinoise set ups due to biomes tags not being used for custom biomes
MC-253096
Mineshafts and strings don’t generate with custom biomes
Resolved
Invalid
0
The biome tags for structure placement should be in
minecraft/tags/worldgen/biome/has_structure; you've put them inminecraft/tags/worldgen/has_structure. It works correctly for me after making that change.