[QoL] Make dropping single items by Z on an inventory slot behave the same as using right click

[valneq]

The keyboard shortcut Z is very convenient to drop individual pieces of coal into burner entities in the early stage of a game.
However, this only works when hovering the cursor over the entity.

If a GUI is open that shows the fuel slot of a burner entity, I often find myself pressing Z while hovering over the fuel slot. However, this drops the coal on the ground as if the GUI was not there at all. This is super unintuitive because from the perspective of the player, hovering over a GUI slot is not the same as hovering over a pixel of ground. In order to drop a piece of coal into the slot, I need to right click while holding the coal. But right clicking on an entity (without GUI) will mine it – independent of any items in the cursor. Consequently, I always need to concentrate and think hard which buttons to press.

If pressing Z on a GUI slot would behave the same as right clicking it, there would be a unified way of dropping individual items. Furthermore, dropping items "through" a GUI is very strange. If not making it behave the same as right clicking, at least disallow dropping items through GUI windows. Maybe with a "forbidden" sound effect and a floating text saying somethig like "press right click to put an item in this slot". Otherwise, people may find random items littered on the ground without really knowing where they come from.