Version information

itemswapper-fabric-0.4.0-mc1.20

Other mods installed

Reproduction Steps

Try inserting an item via ItemSwapper's UI into a shulkerbox.

Crash Report file

crash-2023-06-26_23.27.23-client.txt

Additional information

I'm not sure if this issue is caused by the plugin being outdated or something.

This has nothing to do with the plugin. Somehow the mod failed to grab the shulker data at all(got a size 0 inventory), maybe that shulker was never placed(so it has no data) and I forgot to catch that?

Well, everything's up-to-date.

I'm using Pufferfish if that matters somehow.

Again, nothing to do with the server/plugin.