authentication agent for PolicyKit
PolicyKit-gnome provides a D-Bus session bus service that is used to
bring up authentication dialogs used for obtaining privileges.
This implementation was originally designed for GNOME 2, but most
GNOME-based desktop environments, including GNOME 3, GNOME Flashback,
and MATE, have their own built-in PolicyKit agents and no longer use
this one. The remaining users of this implementation are Cinnamon, XFCE