This can be achieved by setting gsettings key: org.gnome.desktop.background primary-color
However when you select a background image, gnome-control-center resets this key to black.
One option would be to add a colour field to gnome-tweak-tool and disable the reset of the key in gnome-control-center
This can be achieved by setting gsettings key: org.gnome. desktop. background primary-color
However when you select a background image, gnome-control- center resets this key to black.
One option would be to add a colour field to gnome-tweak-tool and disable the reset of the key in gnome-control- center