It’s nothing special. The fridge is just leveled so the hinge is slightly higher on both sides. The door then naturally swings closed. Do French refrigerators have some kind of mechanism that would prevent this? Like a latch of some kind?
We just have them perfectly level, so the door does not move at all on its own.
Weird. Why?
I don't know. When I google this question in French, I see people whose fridge door does close on its own, asking for how to solve this issue; so they must find it inconvenient.