KCM Module to Configure GTK2 and GTK3 Applications Appearance Under Plasma 5 session

kde-gtk-config is a KCM module to configure GTK2 and GTK3 applications
appearance under Plasma 5 session.

Among its many features, it lets you:
 - Choose which theme is used for GTK2 and GTK3 applications.
 - Tweak some GTK applications behaviour.
 - Select what icon theme to use in GTK applications.
 - Select GTK applications default fonts.
 - Easily browse and install new GTK2 and GTK3 themes.