As shown in the picture attached, you can see that the tops of cacti in flower pots under a top slab will not generate the top of their texture correctly.
You can reproduce this bug by placing a flower pot on the ground and placing a top slab above it. Or follow what I do in gif attached below.
(Sorry if that sounds repetitive)
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Sorry bout that, I do not know how to remove my bug report though.
Hi there!
This looks to be a duplicate of MC-195461.