anchor.diff:        "/share/gtksourceview-2.0"
       ];
   
  -    environment.variables = {
  -      GIO_EXTRA_MODULES = [ "${pkgs.xfce.gvfs}/lib/gio/modules" ];
  -    };
  -
       services.xserver.gdk-pixbuf.modulePackages = [ pkgs.librsvg ];
   
       services.xserver.desktopManager.session = [{
  
positive.code:     # Enable helpful DBus services.
      services.udisks2.enable = true;
      services.upower.enable = config.powerManagement.enable;
    };
  }
  
negative.code:       exo
        garcon
        gtk-xfce-engine
        libxfce4ui
        tumbler
        xfconf
  