It is a bit funny, but also very serious.
Thank God no one was killed or seriously injured.
I would guess that they were in a commercial building of some type, not an ordinary house. Such floors are supposed to hold a considerable weight load, something like file cabinets full of paper lined up wall to wall. I seem to remember a number in a building code, something like 700 pounds per square yard, all across the floor.
This sounds like a case where the landlord and the architect have some questions to answer.
I thought Sweden had higher standards of safety.
The good news is no one was badly hurt.
And maybe there is a bit more motivation in the group.
We all know it is tough to lose weight and keep it off.