Is there anyone who uses a door frame?

I like doing pull-ups, but I’m lazy to go to the gym every time.

I was thinking about buying a chining dipping machine, but it took up too much space.

I’m trying to figure out the door frame bars, but everyone says it’s dangerous.

But I can see a product that looks okay because it pushes out more when it’s under the load.

Are there any problems for those who use this? It doesn’t matter if it’s a door frame or something.