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Today I realized that Night Light stopped working in my machine. When I try to set it up, nothing happens. See attached gif:

trying to enable night light

I am not sure what's causing it to fail. I don't know if there are any logs generated by this tool, or if there's another way to enable Night Light.

Any idea what to try? This was working a few months ago.

When I check /var/log/syslog, there are some messages related to night light when I use the «Sunset to Sunrise» schedule, but nothing indicates that it failed:

Sep 19 22:46:37 sambayon gnome-control-c[22940]: no sunset data, using 16.00
Sep 19 22:46:37 sambayon gnome-control-c[22940]: no sunrise data, using 8.00
Marco
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    As a workaround, I have installed the sct program and using it manually, but it would be nice if I could fix Night Light. – Marco Sep 20 '20 at 05:53
  • I just realized that the night light wouldn't show up in a OBS recorded video. Regardless of that, there's no noticeable change in the display color temperature. What happens in the gif, is the same as what I'm seeing on the screen. – Marco Sep 20 '20 at 05:56
  • It happened to me too. I have it set to manual timing, from 05:00 to 04:59. When it broke, even the nightlight icon did not show up in the panel. But I noticed that my monitors (laptop + external HDMI) have disappeared from the Settings app's Color settings sidebar item. I set the preinstalled D50 color profile for my laptop's screen on that Color settings UI. But now only my printer had shown up to set a color profile to: the monitors did not. I think it's related. A reboot however restored everything: the Color settings UI, the laptop screen color profile, and night light. – Levente Feb 28 '21 at 01:57
  • @Levente - you should post this as an answer as it seems to be a solution, and also so it can be voted upon. – Greenonline Feb 28 '21 at 12:19
  • Not only you, and not only 20.04. I just come to notice that night light is out here too! Ubuntu 21.10. – vanadium Feb 20 '22 at 19:53

6 Answers6

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I encountered the same problem in 20.04, so I tried to reinstall gnome-control-center and then tried to restart my computer and it works.

Try running this command in a terminal to reinstall control center:

sudo apt-get install --reinstall gnome-control-center

and then restart you computer.

Greenonline
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Samkit Jain
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    Reinstallation of gnome-control-center is not possible, it cannot be downloaded. for me just restarting my PC solved the problem. – Francesco Borzi Jan 19 '22 at 20:55
  • Worked for me (Ubuntu 22.04 LTS, NVIDIA GeForce GTX 1060 with Max-Q Design, driver 470.129.06). Thank you – KiriSakow Jul 16 '22 at 19:49
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For me, It worked by just rebooting my system.

VARUN JAIN
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For NVIDIA GPU users: I had to reinstall my NVIDIA drivers after a kernel update. You can check if your driver is working with nvidia-smi -- if not, you may need to install drivers.

Łukasz Kidziński
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  • Works for me. I've used this tutorial to make nvidia drivers works: https://linuxhint.com/install-nvidia-drivers-on-ubuntu/ and this to enable change of it: https://askubuntu.com/questions/540862/cant-activate-proprietary-driver-for-nvidia-from-additional-drivers-ubuntu-14 – scorpion Aug 04 '22 at 20:41
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I encountered the same issue in Ubuntu 20.10. After turning on night light, I restart the computer and it works normally.

Nguyễn Đức Anh
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0

Flux was conflicting with the night light program, enabling the Manual mode worked for me.

enter image description here

sotmot
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Manoov
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Try disabling MST in your Monitor's OSD if it has that option.

Multi Stream Transport allows daisy-chaining multiple monitors via display port. I have a multiple-monitor setup and recognized that on the one monitor that has this option night light wasn't working at all.

Hyperplane
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