The following internal class does nothing based on its implementation, which is a pure class wrapper that adds 0 behavior. Including minuscule memory and performance implication, this wrapper slot actually adds minor developmental burden, as all slots in a creative inventory need to derive from it, because mouse interaction casts every slot into a creative slot (again, for no actual reason). For additional headache, the wrapper class inhibits some more specific modding attempts regarding the creative inventory.

net.minecraft.client.gui.screens.inventory.CreativeModeInventoryScreen$SlotWrapper