Setting monitor geometry and physical size for KWin 6 Wayland session

[digitaltrails]

I forgot about this other thread:

To scale or not to scale... confused a bit

I’ve been using a 4K monitor in X11 by setting the KDE font DPI - which has worked quite well for the past few years (after a few adjustments to the panel size, konsole font, and so on). Looking toward a move to Wayland, I noted that setting the font DPI has been removed. I just briefly experimented with scaling on Wayland in KDE 6. It’s a bit confusing. I set the scaling to 150%. Gimp seemed to still show images non-scaled, which is fine, I don’t want images I’m editing to be scaled. But …