From my understanding is that your view from your habitable room cannot be a direct line of sight to your neighbouring habitable rooms.
Our neighbour has a driveway and we have windows that overlook his onto their driveway. I checked with our council and they said that as long as its not a private open space (backyard OR fenced up enclosed area) then it should be fine.
I'm pretty sure this isn't the case. I think there's a distance that's deemed OK between neighbouring windows (for some reason 9m has stuck in my head).
And as others have said, it's first in best dressed. Whoever comes in 2nd has to deal with the problem. There are many screening methods you can use, which mean you don't need to start frosting windows. Timber screening and plants / trees are a much more attractive options.