Armor and elytra duplicates when discarded.

I have experienced twice now that when I remove a piece of armor from my inventory, that piece of armor duplicates, re-entering my left-most hotbar slot. After that there's both that piece of armor and the one you either dropped on the ground or you currently are moving with your cursor.

I am currently not sure how to reproduce this. It seems to occur at random times, but might be dependent on changing between survival and creative mode.

I also had a lot of programs in the background, like OBS Studio, which might have had an impact.