Many post ago, Suz suggested windows
on each side of the seam on the rear. The only problem I see with this is that it would require either curved windows
or a change in the body shape.
I recently looked in a motorhome that had a retractable shower "door"
, which I believe is the same thing that Roger described, although it felt more like a solid film (Roger's term) than a fabric (as described by the Camping World site). I assume it was done to be compact (compared to a rigid door), and it wouldn't billow into the shower space (like a loose curtain), so it made sense to me. It seemed to be easy to use. For those really looking for privacy, I don't know that this would do the trick, as it is only translucent.