Certain items that are 2D in the inventory but 3D when held are not displaying properly. There are "cracks" in the visuals that you can see through.
I have provided some images to show some examples of this effect. Note that these are not the only items this bug is present in. This happens in A TON of various items.
This is a harmless visual glitch.
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-73186, which is a report that has not been resolved yet.
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