conflict between excellentenchants, oraxen, packetevents and protocollib

[thatpris]

• This issue is not solved in a development build

Describe the bug
When BOTH packetevents and protocolib are present, enchants from excellentnenchants cannot be applied to items. Removing either packetevents or protocolib seems to fix the error, so this seems like a conflict between those two.

To Reproduce
Steps to reproduce the behavior:

1. Join with Paper 1.21.1 and all aforementioned plugins
2. Get an enchantment book from ExcellentEnchants
3. Apply it to an item in anvil
4. Bug occurs

Expected behavior
The item should be enchanted normally.

Screenshots

Version Info
https://pastebin.com/ana3vMBx

Additional context
I have tried asking both ExcellentEnchants and Oraxen, and they have concluded that this is a conflict between packetevents and protocolib.

[Ingrim4]

Since we aren't familiar with ExcellentEnchants I think it's best to discuss this in nulli0n/ExcellentEnchants-spigot#143.

[Boy0000]

Issue is likely tracked down to CommandAPI and how it handles datapacks