staff talked about an old dupe

[SpaceGuy119]

This is old news and I'm merely posting to get a better understanding of the background and history.
chris_wilson comments on How cool would it be if Beta keys dropped in game!

Above link shows admission from company staff that there in fact was a dupe going around of some sort. Is anyone aware or could link me to an old reddit/vod/image, or just provide an explanation, of approximately when this was and what the dupe consisted of? I've been playing for years and would love to know, because I wasn't aware of this when it happened..

Thanks.

[ML Infamous]

There have been a number of exploits/dupes in POE.

The first I remember hearing about was people duping items using the MTX "Skin Transfer" and then mirroring the item. There was also the pretty obvious "GCPMan" issue that arose.

Lastly, more recently there was a dupe involving hideouts and the guild stash that was patched rather quickly.