On my 28' sailboat, there is not a lot of room and the most likely
place would be alongside the lifelines inside the shrouds. However,
that would block a lot of light going into the window and block some
ventilation as well.
Daughter had an interesting idea, "hang it over the side". She
suggested putting tubular webbing straps around it and hanging it over
the side from the toe rail. Not sure what to think of this.