So I'm not super sure if this is intended but nether fortress mobs, blaze. wither skeleton etc. cannot spawn on anything besides nether brick. This was not the same in snapshot 21w37a where it was normal.
MC-239631
Nether fortress mob spawning
Resolved
Duplicate
0
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We're tracking this issue in MC-239359, so this ticket is being resolved and linked as a duplicate.
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