Make settings as root

If I have opened an editor as root, is it also possible to make settings there?

For example, if I open mousepad as root, I cannot make any settings, such as line numbers or color highlighting.

Is there a possibility?

…not the best idea (neither is thunar root). There is dbus-x11-git in the AUR, letting you customize thunar and mousepad persistent when using root. But again… it’s not a good idea. Please search the web for more info.

Here is a better idea:

Edit in Nano/Root

Open thunar as normal user - Edit - Configure custom actions
…in the dialog:

Edit in Nano/Root

xfce4-terminal -x sudo nano %f

Appearence Conditions:

File Pattern: *

Appears if section contains: “Text Files” and “Other Files”

…and a nice red terminal icon. -Apply - done.
But careful, much power much damage.

Open thunar as user, create thunar root as described in custom actions, and it will be customizable to a degree. Same with mousepad. Customisation works when opened from this (custom action) thunar root, things like colour, line numbering…