When trying to use the super spyglass with a boat torch equipped, I somehow duplicated my super spyglass. I was holding the spyglass with my cursor and used right click to peer. The animation played but rather open my map and reveal, the spyglass was put back in my inventory and another appeared as well.
EDIT: changed category of bug
I have not been able to reproduce the bug, sorry. Here are all the details of what was going on when this occurred: Walani Armoured Boat IronWind Boat Torch Backpack Probably Pirate hat Either Monsoon or Dry Season Daytime No rain