Pitch-Dark is GNOME Shell extension that forces all application windows to use the dark GTK theme variant.
The most convenient way of installing this extension is using extensions.gnome.org.
The only prerequisite is the xprop utility which can easily be installed using:
- Debian/Ubuntu:
apt-get install x11-utils - Fedora:
yum install xorg-x11-utils - Arch:
pacman -S xorg-xprop
You may also want to install the Adwaita-dark-gtk2 theme that provides a dark variant for Gtk2 applications.
It borrows the guessWindowXID function from mathematicalcoffee's maximus extension.