This can easily be done by anybody. I’m not sure this is so much of an exploit as maybe a tiny inconvenience (lag). Doesn’t PvP have protections against that tho?
Yes, but 99 buckets is a legal stack, so this works. However, it’s only possible on mobile. Mobile also has tons of other useless exploits, like putting multiple identical wings in the vanity slot (yay…) mostly due to the drag-and-drop touch system.