Dragging items that cannot be stacked moves it

When dragging items across a container, non-stackable items (sword, chestplate, cake, campfire, pickaxe, etc.) will move with the cursor instead of remaining where the selection began. On the other hand, items that can be stacked (snow, paper, dirt, etc.) will remain where the selection began, even if there's only one item.

Video Example:

https://youtu.be/68MOb-LLpYo