Mounting a horse in creative mode just before it dies causes a glitch

When you mount a horse in creative mode just before it dies, the game glitches out. When you open the inventory, your character can be seen in the sitting animation, even though the horse is dead. Also, you can walk around, but you can't interact with the world and you can't pick up items. A world reload will fix this issue.

Edit: When the bug occurred for me, the horse drowned in water.