Steps to Reproduce the Crash

1. Pick up any item and bookmark it
2. Throw that item on the ground
3. Hover over where the bookmarked item was

Mod Pack URL (Optional)

https://www.curseforge.com/minecraft/modpacks/seaopolis-submerged

Mod Pack Version (Optional)

1.20.1

Extra Notes (Optional)

Thought it was a one-off thing, but I kept accidentally doing it. Seems to work with removing the item from your inventory in any way (i.e. putting it in a chest). Only tested in singleplayer

Crash Report

https://gist.github.com/Foxboiye/c380cd7f7e0c67ea864a0660a4148af7

Thanks for the report!
Please try updating JEI to version 15.19.5.99 and see if the issue has been resolved or not.
If there is still an issue, please post the new crash report here.