I found a bug that only works on servers for some reason (I am using ketting server 1.20.1)
I have tested this in singleplayer and it does not work, but I also tested multiplayer with no plugins but it still happens

It seems to only work when you apply gems to an item, then spam re equip it.

Video of what happens:
https://github.com/user-attachments/assets/f3e49a44-5cec-4b68-9173-b6386bf5fce2