I’m still on the fence about closing the door for a short task like pouring milk. My understanding from the physics of opening the door, you’re mostly already replacing all the air in the fridge with air from outside the fridge. So convection already did its job of robbing your fridge of cold. Closing the door to open it again a minute later just gives you a second convection inducing action for air that might have been trapped the first time.

I would love to see someone at the level of technology connections do a breakdown of the physics here, and where the likely crossover point point is for different kinds of fridges. My current (probably illformed) belief from the suction and imagined resulting air exchange of all the fridges I’ve lived with is that leaving the fridge open on the order of seconds is better than opening-closing-opening-closing in terms of cold loss.