How to use solid color instead of picture on Ubuntu desktop

Use solid color instead of picture on Ubuntu desktop.

Ensure that picture uri is undefined.

$ gsettings set org.gnome.desktop.background picture-uri ""

Set background color to red.

$ gsettings set org.gnome.desktop.background primary-color "#E66360"

Set background color to green.

$ gsettings set org.gnome.desktop.background primary-color "#6AC46A"

Set background color to blue.

$ gsettings set org.gnome.desktop.background primary-color "#8BC6FC"

Set background color to black.

$ gsettings set org.gnome.desktop.background primary-color "#000000"

It’s a neat functionality.