Closing the UI of a beacon still drops the placed item

The bug

In 1.12 it was made that if you close the UI of a crafting table, anvil, enchanting table etc. the items placed in the slot don’t get dropped. It will go into your inventory and if your inventory is full, it will still be dropped, but for some reason, this hasn’t been changed for beacons.

How to reproduce:

1. Place a beacon
2. Put an item in the slot
3. Close the UI
   The item gets dropped.