macOS (and iOS/iPadOS) is one of the least "technically correct" when it comes to DPI (it uses only the render-at-integer-multiple-and-scale approach) but it do

macOS (and iOS/iPadOS) is one of the least "technically correct" when it comes to DPI (it uses only the render-at-integer-multiple-and-scale approach) but it does support per display settings pretty well. Everything is also built with the assumptions displays will be high DPI so low DPI screens have crap fonts and whatnot. For windows across multiple displays I'd have to check to see the behavior of but I wouldn't hold up hope it's particularly great. Like you say, Microsoft Windows has one of the most ideal technical implementations (fractional per monitor DPI + it at least attempts to display the window across monitors in a way doesn't bitmap scale) and reached this state many years ago but it means nothing if all the apps aren't also updated to support it (much like this article). The cursor thing isn't really to do with DPI, it's a general thing with mixed reported display sizes regardless if they have the same DPI. I wish more systems had the option to cross borders at the relative position between monitors rather than the absolute but neither is necessarily more correct and I'm sure many prefer the absolute method.