1. Go to the Caravan Driver.
2. Have a random item in the 1st inventory tab.
3. Have an item you want to duplicate in the 2nd, 3rd or 4th inventory tab by itself.
4. Hover over an item you want to duplicate and press ⬅️ (left directional) button. Might need to press it two times.
5. Keep pressing ❌ (cross) button.
6. Item gets duplicated with the same stats.
Now you can stash it, sell it for infinite money or duplicate experience potions for easier leveling.
Doesn't require backing up saves and as far as I can tell it works with any item including quest ones.
I don't know if it works on Xbox but it probably should.
Found one other video about this method after I discovered it by an accident but it's on Switch and you have to hold left there I guess.
Ещё видео!