My mother used to put stuck bottle caps between the door-edge and the jamb (on the hinge side) close the door gently, and twist, sometimes standing on one leg so that she could use both hands on the bottle. Using the other foot on the door to apply pressure, of course.
Later on she used a loop of string from the handle, just as efficient but less comical.

It chews up the door edge and closer strip, but the damage makes it more effective.