Another one of my outdoor-tested designs which have defied the elements well. The door stopper is a piece of equipment that helps to hold the door open by using a tension spring. It works best on rough terrains but if you have a slick floor surface try to put rubber to the leg.
You need a 5 cm long spring or in my case 2x one-inch springs. I guess a rubber band will also do the trick, at least for a while. The spring's pivot is slightly off the centre, so it tends to go always into up or down position. It holds firmly in each position – when it’s up, it stays up, and when it’s down, it stays down
The model in the pictures is made of ABS 0.2 layer hight and with 0.25mm printing margin.
Here is a public Fusion 360 link where you may change a printing margin parameter.
May the Spring Force be with you.