off hand, flight duplication bug

If while flying with an elytra you spam click an item in your offhand (Equip it. Then take it off. Equip it again. Take it off again etc etc) the item will either completely disappear, or what will happen far more often is it will duplicate. I have tested the bug and it happens on both single player and realms. It works for any item that can be held in the offhand. Through my tests it does not appear that it happens with any other inventory slots, or armor slots. If i am able to find a way i will record the process and submit a video of it.