Control+Click on empty inventory slot when there arent any

[ichVII]

When you open an entity and control click on an empty slot in your inventory you transfer as many suitable items to the entity as possible. This is a really nice feature. But if your inventory is full, you cannot use it and have to search through your entire inventory to find the correct item. This really annoys me and I dont think Im alone here.

Is there a way to eg have a permanently empty slot in your inventory or an alternate way to activate "control click empty inventory slot"?