Rxgamer

Seems like this bug and MC-29318 are connected in some ways. Or probably the same bug.

Seems like this bug and MC-41113 are similar or probably the same. 

Another way to test this (as this has worsened in 1.13 affecting survival and adventure modes) is by holding an item then asking a friend to clear that item off of you while you are in survival mode.

Or, you can set up a slow redstone clock on a command block clearing your inventory and hold the item before the clock triggers the command block.

Confirmed for 1.13-pre2

Confirmed for 1.12.1

Both invisible and not targetable via @e confirmed in 1.12 now; forgot to test the rest