The middle mouse button cannot be used to copy the displayed item in the trading UI of villagers or wandering traders

Related to MC-270206: The middle mouse button cannot be utilized to copy items displayed in the trading menu.

Steps to reproduce

1. Summon a villager or a wandering trader
2. Trade
3. Hover over a displayed item for a trade
4. Click the middle mouse button

Observation: The item cannot be copied,
Expectation: You should be able to copy the item.