On a 4K monitor with Windows set to scale 150%, I just noticed that the background resolution grid is correct for the 4K monitor, but not so much if you are trying to target the size of a window to a 96 DPI monitor. I thought I would just drag the Studio over to my secondary monitor that is 1920x1200/96 DPI, but the background resolution grid itself is getting scaled by Windows! (I can see the 2560 horizontal marker on this monitor; Windows scales it down 33% because of the difference in scaling between the monitors, 150% vs 100%)

So a windows that is actually 877x706 pixels in size on the secondary monitor appears to not fit on a 1280x1024 monitor according to the resolution grid.

I think the Studio will need to become "per monitor DPI aware" to keep Windows from trying to scale and "fix" the resolution grid.