Currently, the only way to scale windows and window frames is to use the gizmos w/ the stretch property. This is fine for the actual window pane, but when it comes to the frames it makes them look completely horrible and out of proportion because they stretch the size of the frame itself.
In this case the frame is virtually unnoticable at the top/bottom because it’s been stretched the way it is.
There should be an option similar to canvas walls to stretch or shrink the frame (and the window too) without them getting terribly out of proportion. I was pretty surprised this functionality wasn’t here already based on the use of the item, but hey.