Closed Any one know what hacks are in use here?

For a long time now I have seen this player nearly every time I go to sell at the shops, always disguised as a chicken, with a single letter nickname. He is always AFK as he doesn't respond to messages, other than an automated reply. Initially I assumed that he was just using /back as many others do legally however I noticed that when he arrives in front of the sell chest, he always turns to face it which /back does not do. Further investigation showed that he automatically moves around players to reach the chest. He will move multiple times around multiple people to access the chest. He always moves to the exact center of the block and then turns to face the sell sign to sell. This is obviously not a player controlling movement but a script.
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