ubuntu 20.04 无法设置桌面solid-color的问题

gsettings set org.gnome.desktop.background picture-options 'none'
gsettings set org.gnome.desktop.background primary-color '#004000'
gsettings set org.gnome.desktop.background secondary-color '#306030'
gsettings set org.gnome.desktop.background color-shading-type 'vertical'