Item should drop on the ground like in vanilla Minecraft.
Item vanishes completely on death, like the Curse of Vanishing would.
Obtain curse of binding armor. Die. It disappears whether worn or in the player inventory.
Looks like curse of vanishing attributes are being applied to binding. I can supply video if it can't be reproduced, though it should reproduce every time.
Does it work upstream (i.e. Spigot)?
Cooperate needs you to find the differences between curse of binding and curse of vanishing
Paper: They are the same picture
Yes, it does drop correctly under Spigot 1.16.4, just not on PaperMC.
I uploaded a short video to demonstrate this: https://www.youtube.com/watch?v=IHHhFsRB4X8
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Cooperate needs you to find the differences between curse of binding and curse of vanishing
Paper: They are the same picture