I think this might happen because the screen is off at 6am. So any attempt to change the gamma ramps (turn off night light) might fail and not be reattempted. That would be easy enough to fix if it was all in the gnome-shell process, but I suspect some of it is happening in the 'colord' or 'gsd-color' processes. Upstream the GNOME developers have expressed a plan to sort that out:
https://gitlab.gnome.org/GNOME/gnome-settings-daemon/-/issues/131 which might also help with this when done. ** Bug watch added: gitlab.gnome.org/GNOME/gnome-settings-daemon/-/issues #131 https://gitlab.gnome.org/GNOME/gnome-settings-daemon/-/issues/131 -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-shell in Ubuntu. https://bugs.launchpad.net/bugs/1894596 Title: Night Light stays on Status in gnome-shell package in Ubuntu: New Bug description: I have "Night mode" set to turn on every day at 10pm and off at 6 am. However, at 6, the "Night mode" icon disappears but my screen remaine orangeish as when "Night mode" is on. Logging off and on again restores color temperature back to normal. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: gnome-shell 3.36.4-1ubuntu1~20.04.2 ProcVersionSignature: Ubuntu 5.4.0-45.49-generic 5.4.55 Uname: Linux 5.4.0-45-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.8 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: GNOME Date: Mon Sep 7 07:43:43 2020 DisplayManager: gdm3 InstallationDate: Installed on 2020-04-11 (148 days ago) InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Beta amd64 (20200409) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=fr_FR.UTF-8 SHELL=/bin/bash RelatedPackageVersions: mutter-common 3.36.4-0ubuntu0.20.04.2 SourcePackage: gnome-shell UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1894596/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp