This is how we used to dupe on private servers
Doesn't work on a lot)
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1. Make two accounts, and log in both.
2. Put up item you want to dupe and click accept on the account sending it.
3. Right click on the item, and then accept on the other account.
4. Click remove item, and it should appear in your inventory(I think).
5. Accept the trade and you should both have that item.
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