If a single unenchanted tool is placed into the input slot of a grindstone, the tool appears in the output slot and can be selected, even though the tool did not have any enchantments or need any repairs.
Steps to Reproduce:
- Place down a grindstone.
- Open the grindstone GUI.
- Place a single unenchanted tool in the input slot.
The tool appears in the output slot and can be selected despite it being unenchanted and fully repaired.
The tool doesn't appear in the output slot and an "X" is placed over the arrow.