When playing on a server I encountered an issue where after placing items in a barrel and picking it up by breaking it, it saved the items inside. I assume that's a feature as the block also had a tool tip naming the contents. After noticing that there was an item in my hand(from left clicking it to break it) I attempted to break it again by holding shift(hoping no items would pop out. To my dismay I got the barrel with no items inside and it locked its self. I don't mean the locking mechanism that is supposed to happen. I mean that the tool tip says nothing about the type or amount of items stored inside and when placing it down there is nothing inside the barrel. Upon inspection of the NBT data I can see that there is still an item count.

I tried this with something in my off hand and not. It still "locked" the barrel.
If you need me to get any other information please let me know.

[YABBA Version: 1.11.2-0.5.1]