Night Light occasionally gets stuck

[Kevin Keijzer]

[ Impact ]

Since installing Ubuntu 24.04, every now and then Night Light gets stuck when my screen is locked at night and I unlock it in the morning. The screen is then very orange (more so than normally is the case with Night Light), and disabling it with the button in in the top bar menu does nothing.

The only ways to restore the screen to normal are disabling and enabling the colour profile or running `gdbus call -e -o /org/gnome/SettingsDaemon/Color -d org.gnome.SettingsDaemon.Color -m org.gnome.SettingsDaemon.Color.NightLightPreview 1`

[ Test Plan ]

Unknown. Requires OP verification.

[ Where problems could occur ]

Night light and colour profiles are one in the same feature so touching one always risks affecting the other. Since all such gamma changes get committed along with other screen updates, there is the risk (particularly with atomic mode setting) that a mistake in any one change will cause the entire screen update to fail, resulting in black frames.

[ Other Info ]

I have never been able to find anything remotely relevant in any system logs regarding this issue. It also does not happen every day, but probably once every seven to ten days or so.

My PC has an AMD RX550 GPU using the amdgpu driver. I'm not sure if it makes a difference, but so far I've not seen this problem on my other machines with Intel IGPs.

The upstream bug report can be found here: https://gitlab.gnome.org/GNOME/mutter/-/issues/3439

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 46.2-1ubuntu1

---------------
mutter (46.2-1ubuntu1) oracular; urgency=medium

  * Merge with Debian. Remaining changes:
    - Add x11-Add-support-for-fractional-scaling-using-Randr.patch
    - Add window-Add-ability-to-override-the-edge-constraints.patch
      + Make possible for extensions (such as Tiling Assistant) to override
        window constraints
    - Ignore test results on armhf & ppc64el

mutter (46.2-1) experimental; urgency=medium

  [ Daniel van Vugt ]
  * New upstream release 46.2 (LP: #2068598)
    - Fixed mouse clicks falling through to the window behind (LP: #2026194)
    - Fixed a crash in meta_wayland_transaction_commit (LP: #2061739)
    - Fixed night light getting stuck on (LP: #2066902)
  * Update Support-Dynamic-triple-double-buffering.patch:
    - Removed bogus changes introduced in 46.1-2 (unrelated files)
    - Fixed debugging mode "MUTTER_DEBUG_TRIPLE_BUFFERING=always" which had
      temporarily stopped working in 46.1 but also nobody should have been
      using it.
    - Updated commit message to mention the upstream source is maintained
      in 'triple-buffering-v4-46'.
  * Refreshed patches:
    - meson-Do-not-mark-CI-test-tools-as-required.patch
    - Mark-several-additional-tests-as-flaky.patch
  * Add clutter/conform gesture tests to the list of known flaky ones:
    it is a new test in mutter 46
  * Add patch to compile gsettings schemas for use in build tests

  [ Jeremy Bícha ]
  * Stop compiling gsettings schemas in debian/rules
  * Opt into Salsa CI

 -- Jeremy Bícha <email address hidden> Wed, 12 Jun 2024 16:30:58 -0400

[Timo Aaltonen (tjaalton)]

Hello Kevin, or anyone else affected,

Accepted mutter into noble-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/mutter/46.2-1ubuntu0.24.04.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-noble to verification-done-noble. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-noble. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Kevin Keijzer (kkeijzer)]

I have installed the mutter package from noble-proposed and rebooted, so I'll be testing it from now on.

kevin@arcadia:~$ mutter --version
mutter 46.2

Sadly I don't know of any way to manually trigger this bug. Sometimes it doesn't happen for days, and then all of a sudden the colour temperature is stuck again when I unlock my computer in the morning. I haven't discovered any pattern or causality.

So I guess the only way to test this is to just wait and see if it doesn't happen any more.