[Bug]: Ender shelf sometimes deletes enchantments when mined.

[kalutro]

Minecraft Version: 1.16.5

Forge Version: 36.2.29

Mod Version: 1.5.15

Single Player or Server: Single Player

Describe problem (what you were doing; what happened; what should have happened): Ender shelf sometimes deletes enchantments when mined.

1. Put enchantment into the an Ender Shelf. Doesn't matter which enchantment or which slot.
2. Mine the Ender Shelf along with another Ender Shelf. It doesn't seem to matter in which order the shelves are mined. 2a. Sometimes the shelves will enter different slots in my hotbar, which I assume is normal. Sometimes they stack, which I assume is abnormal.
3. Place shelves back down. If the shelves stacked in my hotbar, they will both be empty.

Please note that this doesn't happen every time. It doesn't seem to matter which enchantment is used, which slot it's placed in, in which order the shelves are mined, in which order the shelves are placed, whether they are connected to a controller, or whether the second shelf is empty or has enchantments in it.

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