[rwha]

Xft.dpi: 192 in ~/.Xresources should do it for most things. I know chromium and firefox do now. However I couldn't get (u)rxvt to scale. The i3 docs [0] also state a font that scales is needed (e.g., *.font: pango:somefont in ~/.Xresources).

[0] https://i3wm.org/docs/userguide.html#hidpi

[usr1106]

"Xft.dpi: 192" in .Xresources is recommended everywhere. However, when the desktop under Xbuntu starts it turns out that this setting has been ignored (or overwritten later). Haven't found out why. Other settings in the same file work as they should.

So this is the standard Xfce desktop, maybe I should try with i3. I use i3 at work, but xfce at home. No exact reason why, maybe it's just good to know more than one systen :)