Thanks for reporting this issue. Unfortunately, there isn't anything that can be done about this specific bug. When you run an application as root, you lose some environment variables. In particular, the XDG_ variables that are loaded in the user session are not carried to the root session.
XDG_DATA_DIRS=/usr/share/xubuntu:/usr/share/xfce4:/usr/local/share:/usr/share:/var/lib/snapd/desktop:/usr/share Our default application associations exist in /usr/share/xubuntu/applications/defaults.list. Without those defaults, any application registered for text/plain can open it by default. I think they're evaluated alphabetically. ** Changed in: xubuntu-meta (Ubuntu) Status: New => Won't Fix -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2020921 Title: .CONF files default to opening in LibreOffice rather than Mousepad when running Thunar as root To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xubuntu-meta/+bug/2020921/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs