Hello.
I've been playing with a few friends on a custom-made modpack that has been evolving over time, with gaining and losing mods. And one friend noticed a problem with building gadgets, most likely related to a removed mod. He was storing blocks in the pocket storage, and now just noticed, that he has empty slots (presumably spots of removed blocks/changed block ID from other mods) that are locked, and can't have anything inserted in them.

Is there something I'm missing, or is this a bug/unfixable?

Thanks for any help!

Oh interesting, so items in the storage from a mod that was then later removed? that might cause an issue, ill look into it.

Sorry, forgot about this bug for... awhile... fixed in 1.21, ill try to push fixes out to older versions when i have the energy... b553e3a