KDE systemsettings: missing button / behaving differently when run as root

given the different level of power root has and the file ownership challenges that could be introduced?

Well, sometimes a regular user operation can be much more devastating than a root operation, because sensible data are always stored in HOME folder and not in any system folder, and if a user has access to root password then he is the only responsible for his actions.

I used many apps as root for years and no problem occurred.

And concerning theming, it can be annoying if you have a nice dark Breeze theme applied to all your opened apps then suddenly a white app appears on the screen, your eyes will surely hurt after using it for long time.

I wished if Plasma settings could apply the same dark Breeze used by regular user to root but with additional red titlebar and/or red frame or shadow to make them distinct without hurting user eyes.