The luminous feature was introduced in GNOME 3.24 to switch your display to warmer colors at night to help you sleep better and prevent eye fatigue.
You can enable the GNOME Night Light option from
Settings -> Displays -> Night Light -You can choose to run it automatically based on sunset / sunrise time or enable it on a manual schedule, and also control the color temperature. If you want to extend the “Night Lights” feature to automatically switch to the dark Among the variants of the GTK theme you are using when “Night Lights” is launched, there is a GNOME Shell extension to do this. When “Night Lights” is turned off (by you or by the schedule you set in GNOME settings), the theme will switch back to the regular GTK theme variant.
The extension Night Theme Switcher, And using it, you will get a combined night light and dark mode, which will be set automatically based on the sunset / sunrise time of your area of residence. This is what the extension does. Apart from installing extensions and enabling the GNOME Night Light option, there are no settings or anything else you need to do. This extension requires GNOME Shell 3.28 or later.
In order for this extension to work, the GTK theme you use on your GNOME desktop must have
Yaru-dark E.g. Themes known to work with this GNOME Shell extension include Adwaita (the default GNOME theme), Arc, Materia, HighContrast, and Yaru (the default Ubuntu 18.10+ theme).
It’s worth noting that Night Theme Switcher does not change the GNOME Shell theme (for example, panels and menus accessed from the GNOME Shell panel). So for best results, use a dark GNOME Shell theme. If you are using Ubuntu 19.10, see here how to use the Yaru Shell theme to get dark GNOME Shell menus and dialogs. To install Night Theme Switcher, follow GNOME Shell Browser integration instructions If you haven’t, go to Night theme switcher page On the GNOME extension website. Next, click
OFF Switch to the right of the extension to open it
ON And install the extension.