In the Creative mode inventory, using the number keys on the keyboard to move an item from one slot in the hotbar to another (still in the hotbar) doesn't work as it should.
The item appears as if it moved, but it acts like the item that was in the same slot before it.

For example, If I have "Bow" in slot one and a "Stone" in slot three, highlight slot three, and click "1," the two items visually switch places, but the "Stone" acts like a bow and shoots arrows, while the "Bow" continues to function properly.

Also, it's worth noticing that this glitch doesn't occur in the Survival inventory or if you're in the "Survival" tab in the Creative inventory; however it does occur in all the other Creative inventory tabs.