Some of these methods have a problem. They are basically air tight, and will block air circulation. Since I hang a blanket that is porous to air over the door, and have the bathroom fan (Something I added to this old apartment, and made sure was light tight when I did.) there is air flow through the makeshift darkroom.

I do not think I would want to try and work in a darkroom with plastic over the windows and door, nor do I think weather stripping is a good idea. A sweaty, airtight, room filled with noxious fumes does not seem like a good place to work.