The bug
The top of the cactus texture (when in a flower pot) does not appear when there is a slab on the top half of a block above it, however it is normal if there is not a slab above it.
Linked issues
is duplicated by 28
relates to 2
Attachments
Comments 12
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Can confirm this is the case for 1.16.2, at least. This is without a resource pack, but with the OptiFine mod installed. Will check without after.
EDIT: It also occurs with 1.16.2 and 1.16.3 without OptiFine.
I can't reproduce this, are you using a texture pack? Also show your F3 debug menu.