Go inside a building with several floors. Go upstairs(dont think the elevation matters). Now when you open your inventory while physically touching an object in that room(the wall for example, or a bed) you will die/break your legs.

This does not work with all objects or in all buildings. It is seemingly random but seems to only occur on upper floors inside a building and exclusively while on the inventory screen. You can stand next to virtually anything and nothing happens as long as you dont open your inventory.

A few places it happened for us: Residential buildings in towns at the stairs; The air control tower on the north-west airfield next to that little desk and outside while touching the metal fence; The military prison building on airfields and such upstairs when youre in between the door and the bed to the right of it.