While recklessly installing/testing some new themes I broke my GUI. Nothing seemed to be working right. After rebooting the box I was sitting at a blank screen. A quick check of ps -aux showed Gnome and Xorg running. What gives?

Fired up journalctl and saw a bunch of these listed. Yep that looks like a place I might have screwed up.

gnome-session[7460]: Window manager warning: Failed to load theme "Adwaita": Failed to find a valid file for theme Adwaita
gnome-session[7460]: Window manager warning: Failed to load theme "Simple": Failed to find a valid file for theme Simple
gnome-session[7460]: Window manager warning: Failed to load theme "ThinIce": Failed to find a valid file for theme ThinIce
gnome-session[7460]: Window manager warning: Failed to load theme "Zukitre": Failed to find a valid file for theme Zukitre
gnome-session[7460]: Window manager warning: Failed to load theme "Default": Failed to find a valid file for theme Default
gnome-session[7460]: Window manager warning: Failed to load theme "Emacs": Failed to find a valid file for theme Emacs
gnome-session[7460]: Window manager warning: Failed to load theme "Redmond": Failed to find a valid file for theme Redmond
gnome-session[7460]: Window manager warning: Failed to load theme "Moka": Failed to find a valid file for theme Moka
gnome-session[7460]: Window manager warning: Failed to load theme "Numix": Failed to find a valid file for theme Numix
gnome-session[7460]: Window manager warning: Failed to load theme "Zukitwo": Failed to find a valid file for theme Zukitwo

I quick Google search found a recommendation to reinstall the gnome-themes-standard package.

$ sudo pacman -Sy gnome-themes-standard

The package spit out a couple warnings..

pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/backgrounds/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/metacity-1/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-3.0/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-2.0/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-2.0/Arrows/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-2.0/Buttons/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-2.0/Check-Radio/
          filesystem: 766  package: 755
pacman[7583]: warning: directory permissions differ on /usr/share/themes/Adwaita/gtk-2.0/Entry/
          filesystem: 766  package: 755

ok.. someone fat fingered the permissions.

$ sudo chmod -R 755 /usr/share/themes
$ sudo systemctl restart display-manager

Everything is back to normal.. The take away is use ~/.themes or be more careful. :)