As seen in the picture, redstone, and other blocks can be put on shelves
To do glitch: put a block that usually isn’t able to be placed on a non full block on top of shelves
Expected: the blocks are not able to be placed
For the 1.21.110.25 Preview, the blocks cannot be put on and below the shelf in all orientations, but ladders are still able to be placed on the side, carpet like blocks (such as the pale moss carpet) can still be placed on top and banners can be places on the top and all sides.
For the 1.21.110.26 Preview:
Banners can still be placed on top and on all sides of a shelf in all orientations.
(Expected: only the back of the shelf)
Grindstones can be placed on top and consider the shelf as a block (though may be intentional).
Paintings and item frames can be placed on all sides of a shelf in all orientations.
(Expected: only the back of the shelf)
Signs can be placed on top and on all sides of a shelf in all orientations.
(Expected: only the back and sides of the shelf)
Cake can be placed on top and consider the shelf as a block.
(Expected: cannot be placed)
Linked issues
is duplicated by 4
relates to 2
Attachments
Comments 8

<no repro>
Does this issue occur on specific place on the shelfs?
Does the blocks need to be near any other blocks?
This ticket will automatically reopen when you reply.
Blocks that need support (such as redstone torches) can be placed above a shelf when “minecraft:cardinal_direction”=“south” for the shelf
Blocks that need support on the sides (such as ladders) can be placed on all sides in all shelf orientations.
Blocks that need support above (such as lanterns) can be placed below a shelf when “minecraft:cardinal_direction” is either “east” or “west”
Whether the shelf is touching other shelves or if there are blocks beneath a shelf does not matter
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