Xorg does per-monitor DPI and per-monitor refresh rate. Debian probably never shipped a version that does, but it works fine on Gentoo Linux.

I've tested per-monitor DPI before, and [0] mentions one way to do it. I tested per-monitor refresh just now. Using the xrandr CLI to set the refresh rate to 24.0 on my primary monitor and 60.0 on my secondary results in "cinematic" visuals on the primary monitor and "soap opera" visuals on the secondary.

I'm currently using Windowmaker, but I see no reason why this wouldn't work with KDE.

[0] <https://news.ycombinator.com/item?id=48533247>

Maybe it's possible now. It wasn't back when I last used X. Now that Wayland is the default on most distros and works on nvidia now I don't see any reason to go back.

Good for you? But mixed-monitor DPI and mixed-monitor refresh rate haven't been key selling points of Wayland for like eight to ten years, at least.

It has been nearly eighteen years since the Wayland project started, and they are still not at feature parity with the major windowing systems. [0] It's nuts how long it's taking them. [1]

[0] As one example, apparently the Wayland policy for clients that stop responding for a few seconds and fill up their event mailbox is still to terminate the stuck client. If memory serves, Windows 9x handled stuck clients better than that.

[1] I'm sure it's good enough for what you're doing and you never run into any rough edges or misfeatures, so don't bother chipping in with that retort. ;)

I agree it used to be fiddly at best but in recent years I had found it to be pretty easy in X11.

I haven't had complaints there for Wayland but I will say that it breaking other things has been annoying.