If I open a container and try to drag&drop it inside itself, there is an error message preventing such.
If I open a container, then open a container inside it. I can drag&drop the container in the nested one, they both lock and disappear once I close them.

Open A -> Drag&Drop A inside A -> Error Message -> Good.
Open A -> Open B that is inside A -> Drag&Drop A inside B -> Goes bad, really bad.

I've no clue where the items are now, destroyed? Locked in memory? No idea.
Update: The items are destroyed. Nowhere seen in totalRP3.lua where inventory is stashed.

Solution proposed: It should test recursively if a container adds itself into itself or nested containers.

This is a pretty nasty bug because it can happen easily.