It's not that it doesn't work at all, and it might even work pretty well in most apps. The problem with non-integer scaling is the moment you run an app that h

It's not that it doesn't work at all, and it might even work pretty well in most apps. The problem with non-integer scaling is the moment you run an app that has a custom UI element that thinks in pixels you start having to do ugly things. There's a reason even Apple chose to implement their "Retina" displays by doubling the DPI compared to their predecessors. It makes backwards compatibility so much easier. All the system-provided UI elements can work at the new resolution while the custom elements get doubled unless they explicitly declare hiDPI support. AFAIK if you use a non-Apple display on a Mac or set it to a non-standard scaling factor it's still implemented by using a virtual display resolution that's higher than the actual display resolution where legacy apps still get doubled and then the resulting image is scaled back down to the actual display which gets the best possible result at the cost of processor/GPU resources. Windows and Linux to my knowledge use "cheaper" but significantly uglier methods (also seen on Macs when using X11 apps).