Something I have noticed on several occasions while playing on experimental; When you go into your inventory and drag something out of your inventory (click and drag) the item won't appear in your vicinity.
First I thought the item had just dissapeared but I discovered it doesn't dissapear, but the item will be warped somewhere behind you, some 10-15 meters behind you.
This has happened to me quite some times inside various buildings (police station, pub)
not: this is not the same as items falling through the floor/ceileing when you drop an item inside a building on the first/second floor.