Losing items from crafting table

If you place items in the crafting table or in the 2x2 crafting place in your inventory, and then press F6 you will get a warning about "Twitch Broadcast not available". If you then press ESC you will loose all the items placed in the crafting table.

What I expected to happen was...:
I thought that the items would return to the inventory when closing the warning dialogue.

What actually happened was...:
I lost all the items placed in the crafting table.

Steps to Reproduce:
1. Open the crafting table.
2. Place some items there.
3. Press F6 and then ESC.
4. Your items are now gone.