As the title says. A long time ago it was possible to do this running qtconfig as root. Now it seem to have changed but after Save & Exit, and starting Yast, it sill use the 9 point (I think) default font.
Well, I logged as root (please don’t kill me :)) and changed fonts in qtconfig (or was systemsettings? I already forgot). Then logged back to my normal user and Yast fonts were larger. So I suppose it still does.
Well Yast runs under root and all root users settings are stored in /root (not the home directory) this includes all GUI settings. You can run systemsetting5 as root to set your GUI stuff for any program that runs as root. I change the colors so any program running as root looks different
Point is that some display settings like desktop preferences settings are user defined and root is a user, just a very privileged one. So changing settings for a normal user or even for system does not change settings for the root user. The changes must be set in /root for the root user owned windows.
Yes, that is understood. What is curious is that even changing user systemsettings, root systemsettings, qt5ct and qtconfig some applications (nvidia-settings and firefox as noted above) still show small fonts.