Bug 419690 - Night color setting doesn't extend to external monitors
Summary: Night color setting doesn't extend to external monitors
Status: RESOLVED FIXED
Alias: None
Product: systemsettings
Classification: Applications
Component: kcm_nightcolor (other bugs)
Version First Reported In: 5.18.4
Platform: Fedora RPMs Linux
: NOR normal
Target Milestone: ---
Assignee: Plasma Bugs List
URL:
Keywords: multiscreen
: 481269 (view as bug list)
Depends on:
Blocks:
 
Reported: 2020-04-05 17:54 UTC by bhaskarsmanda
Modified: 2025-08-20 16:54 UTC (History)
9 users (show)

See Also:
Latest Commit:
Version Fixed/Implemented In: 6.3.5
Sentry Crash Report:

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Description bhaskarsmanda 2020-04-05 17:54:09 UTC 
When a second monitor is connected via HDMI, the night color setting doesn't extend to it. Have to unset "Activate Night Color", and re-set it, then it extends.


STEPS TO REPRODUCE
1. Connect HDMI monitor, observe color temperature is much higher that on notebok screen which has night color operation mode "Constant".
2. Uncheck "Activate Night Color", "Apply", check it again, "Apply".
3. Both monitors display a lowering of color temperature.

OBSERVED RESULT
Notebook display is in night color mode,  monitor connected via HDMI cable is not.

EXPECTED RESULT
Night color mode should apply to connected external monitors too.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.67.0
KDE Frameworks Version: 5.67.0
Qt Version: 5.13.2

ADDITIONAL INFORMATION

Upon request.
Comment 1 Daniel 2020-07-14 21:47:41 UTC 
Can confirm. If you attach an external screen, after the night color has kicked in, the color of the new screens isn't updated.
Comment 2 Magno Lomardo 2020-11-08 20:28:01 UTC 
Can confirm.

In my case the Night Color goes off immediately after the "night color tab" is no longer in focus. 

I am experiencing this on a desktop, using a NVIDIA 550ti with monitors on both HDMI and VGA ports. 
For my case, it does not matter if the monitor is the primary display or not, the one at the VGA port always get the "night color" disabled once the "night color" configuration tab loses focus.
Comment 3 Aaron Wolf 2024-03-04 04:20:46 UTC 
*** Bug 481269 has been marked as a duplicate of this bug. ***
Comment 4 Nate Graham 2025-08-01 22:27:26 UTC 
This has been working for me for quite some time now. Is anyone still able to reproduce it in Plasma 6.4 or later?
Comment 5 Bug Janitor Service 2025-08-16 03:46:26 UTC 
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 6 Magno Lomardo 2025-08-19 18:08:23 UTC 
It still glitches occasionally. The more likely scenario for it to happen is when the laptop is already powered and then I connect the other monitor.
A particular case that seems problematic is when you connect a TV using HDMI. I will perform some tests later tonight and share the results.
Comment 7 bhaskarsmanda 2025-08-19 23:16:15 UTC 
Unable to reproduce/is working OK in Plasma 6.3.5 in Fedora 41.
Comment 8 Nate Graham 2025-08-20 16:54:29 UTC 
Great, thanks for following up!