The Orange Glow
Ubuntu features a built-in “Night Light” function, similar to f.lux or macOS Night Shift. This feature is designed to reduce eye strain and improve sleep quality by automatically reducing the amount of blue light emitted by your monitor as the sun sets, giving your screen a distinct, warm orange tint. While excellent for late-night coding or reading, this automatic color shift is catastrophic for graphic designers, photographers, or video editors who require absolute color accuracy on their calibrated displays. If the screen suddenly turns orange at 7:00 PM, all color grading work must immediately halt.
Deactivating the Color Shift
To ensure your monitor colors remain perfectly accurate and to stop Ubuntu from automatically activating the Night Light schedule, you must completely disable the feature within the display settings.
Click on the system menu in the extreme top-right corner of your screen (where the network and battery icons are located) and select Settings. In the left-hand navigation sidebar, click on Displays. In the main right-hand panel, look near the top for a tab or button labelled Night Light. Click on it to open the specific color temperature controls. At the very top of this new window, you will see a master toggle switch. Click the toggle to turn it Off. (You do not need to adjust the “Schedule” or “Color Temperature” sliders; turning the master switch off overrides them). The orange tint will immediately vanish, and Ubuntu will no longer attempt to adjust your screen’s color profile based on the time of day.