You cannot copy displayed items in the stonecutter UI using the middle click

Related to MC-270206: It's not possible to copy displayed items in the stonecutter UI using the middle click.

steps to reproduce

1. Place a stonecutter
2. Place an item into the slot
3. Hover over an item displayed for stonecutting
4. Click the middle mouse button

Observation: Items displayed there cannot be copied,
Expectation: You should be able to copy items that are displayed there.