The bug
Mesa surface mineshafts always cave_air, even if the mineshaft piece did not place any blocks because it would be floating, see
[media]
.
How to reproduce
Create a world with the following seed
-9144014475768710727Teleport to the mineshaft
/teleport -126 90 162Download the attached datapack
[media]
and place it in the
datapacksfolder of the worldReload the datapacks
Use the provided function to mark
cave_airblocks/function marcono1234:replace_cave_air
Affects 18w22c