The more you move it around, the longer it will take to fully heal. If you were to immobilize the joint with an athletic wrap/tape, it would probably be fine. Without that, I'd imagine it would be hard to keep it from moving while swimming.
I don't know where you're from, but the vast majority of cars in the US have hollow doors. The only exceptions might be expensive luxury cars. There is no foam in them. If you poured milk in them it would most likely drain out of small holes in the bottom, although it might splash & stick to some of the internal components and make a smell.
About 23.5" of snow has fallen between now and the previous weekend. Travel is returning to winter normal, but is definitely still difficult.
Last time I participated (previous election) the line for the sign-in/registration table went outside and I had to wait ~5 min. to get inside.
They all follow that general form because the same company (Match Group) bought all of the different dating sites and changed them to the form that makes them the most money.
To be fair that's pretty much what I do here in the US