Using middle mouse button to copy a block shows different results in hotbar and inventory

Verification builds: 1.2 / 464771

Summary: Using middle mouse button to copy a block shows different results in hotbar and inventory

Impact: Can be a little confusing

Repro Steps:

1. Use middle mouse to clone a block
2. Check that the block has cloned in your hotbar
3. Check inventory UI and notice the same position on the hotbar shows a different thumbnail, despite showing the correct item name

Observed Results: Item is being cloned but the inventory UI is stale and needs refreshing

Expected Results: Should show the correct thumbnails in the inventory UI

Screenshots/Videos attached: Yes