Reproduction steps

1. Hold a Wand
2. Open Spell Menu
3. Open Inventory
4. Click at the Wand and press F at the same time

Result: There will be Two Wands on both hand

Environment details

Magic Version 8.3
Yatopia Build 19

Related issue; open ocarina, throw ocarina on floor with q. now there is 2 ocarina. repeat for infinite profit.

Looks like these were a side-effect of a fix for a different dupe exploit. Gotta love Minecraft.

I'm pretty sure it's fixed. I was able to do the click+swap dupe one time, but the item I got was a virtual client-side item that disappeared when I swapped the real one back to my hand.

I think I have it fixed in the latest dev/stable builds if you can try it out.

unable to recreate in latest, it's fixed.

Great, thank you for letting me know!