Gifting a stimm to a player as soon as they loot another stimm will cause the stimm they looted to disappear, but they will still receive the stimm that was gifted to them.
Steps to Reproduce (Required):
On any map, simply gift a stimm to another player as soon as they loot another from the map.
Edit: In case of scriptures it’s an exploit (still counts for progress and rewards) in case of rest it’s a bug - you can’t use other consumable that “disappeared”,
Something tangentally related is that 2 people can try to fix an interrogator at the same time and one person’s inputs will affect the other person’s attempt and vice versa.