Now they are, and I've taken a couple of photos, showing what this piece of wood is designed to do. But first, let me back up and define the problem. If you have cats, you'll understand immediately.
As a temporary measure, I've been using expandable half-screens, which work fine up to a point. Setting aside aesthetic considerations, a not inconsiderable issue, an expandable screen a) does not provide quite enough peace of mind for the cat owner who loves to feed birds in the backyard, and b) cannot prevent bugs from flying up over the screen and down into the window. Many a time, I've come into the bathroom (where this actually quite charming, old expandable screen is installed) to find a moth or other large bug fluttering or zooming around the room.
Personally, my bigger worry is the cats. Phantom, my trusty model, will demonstrate.