I purchased a prehung fiberglass door that has been primed. Should I paint the door before it is installed? I am concerned about getting paint on the jamb.
Thanks

You might scratch the paint hanging the door. Hang the door, wait till the summer heat and humidity drop and paint the door in place.

Install door and frame. Remove door by removing hinge pins. Remove all hardware and paint. Assuming you will use latex paint, let door dry for a couple of hours before reinstalling. Dry to the touch (30 minutes ) is not the same as dry to handle (2 hrs). After reinstalling the door, tape or staple strips of wax paper to the frame at all places where door and frame come into contact with one another to prevent transfer of the paint to the frame. It takes several days for latex paint to completely dry.