The latest 1.2.10 update to the mod seems to have broken blockstate culling for some blocks. So far I have only noticed it with stairs.

BlockState Culling Off

BlockState Culling On

Also happening with cherry trapdoors.

can you say how to reproduce it, doesn't happen with just moreculling (or test latest commit yourself), i think i found the fix but need to test

That fixed the step issue. The issue with the cherry trapdoor still occurs, and only with that trapdoor. I am using the reimagined resource pack.

It also only occurs when the trapdoor is open against a block.