SUMMARY Setting the global theme to automatically switch doesn't cause the theme to switch. Happens both with custom times or location based day/night cycle settings. Night light responds to the day-night settings. Operating System: KDE Linux 2025-09-17 KDE Plasma Version: 6.4.80 KDE Frameworks Version: 6.19.0 Qt Version: 6.9.2 Kernel Version: 6.16.7-arch1-1 (64-bit) Wayland
I don't know if these are relevant, but: Switching to dark mode and then to automatic sets it to Breeze Light.
Works for me; I've been using it for a month or so. How are you setting this up? From Quick settings, or the Global Themes KCM? What's your time zone, and have you changed it recently? Are you making sure to wait 5 seconds after the configured switching time is reached? BY default, it requires 5 seconds of inactivity before switching (this is configurable). If you restart KDED with `systemctl restart --user plasma-kded6.service`, does it start switching at the correct times?
(In reply to Nate Graham from comment #2) > Works for me; I've been using it for a month or so. > > How are you setting this up? From Quick settings, or the Global Themes KCM? > > What's your time zone, and have you changed it recently? > > Are you making sure to wait 5 seconds after the configured switching time is > reached? BY default, it requires 5 seconds of inactivity before switching > (this is configurable). > > If you restart KDED with `systemctl restart --user plasma-kded6.service`, > does it start switching at the correct times? I tried setting it up from both pages. The timezone hasn't ever changed on this device: CET. I forgot and didn't wait, but if I wait or uncheck the inactivity checkbox, it still doesn't change. Restarting kded solves it.
Now that it's working, if you reboot the machine, does it stay working?
(In reply to Nate Graham from comment #4) > Now that it's working, if you reboot the machine, does it stay working? No, and apparently restarting kded6 doesn't always solve it
Gross, bugs like this are just the worst!
Can you try running plasma-apply-lookandfeel --keep-auto --apply org.kde.breeze.desktop and plasma-apply-lookandfeel --keep-auto --apply org.kde.breezedark.desktop do they change anything?
(In reply to Vlad Zahorodnii from comment #7) > Can you try running > > plasma-apply-lookandfeel --keep-auto --apply org.kde.breeze.desktop > > and > > plasma-apply-lookandfeel --keep-auto --apply org.kde.breezedark.desktop > > do they change anything? I turned on the day-night theme during the day, and it changed correctly to light. However, setting the sunset time to earlier than the current system system didn't cause it to change, and plasmashell crashed: https://crash-reports.kde.org/organizations/kde/issues/260506/events/9817dc44dcbe4c7a9dddfd28aa382f1f/ Running `plasma-apply-lookandfeel --keep-auto --apply org.kde.breezedark.desktop` caused the theme to change as expected :)
(In reply to aronkvh from comment #8) > (In reply to Vlad Zahorodnii from comment #7) > > Can you try running > > > > plasma-apply-lookandfeel --keep-auto --apply org.kde.breeze.desktop > > > > and > > > > plasma-apply-lookandfeel --keep-auto --apply org.kde.breezedark.desktop > > > > do they change anything? > > I turned on the day-night theme during the day, and it changed correctly to > light. > However, setting the sunset time to earlier than the current system system > didn't cause it to change, and plasmashell crashed: > https://crash-reports.kde.org/organizations/kde/issues/260506/events/ > 9817dc44dcbe4c7a9dddfd28aa382f1f/ > Running `plasma-apply-lookandfeel --keep-auto --apply > org.kde.breezedark.desktop` caused the theme to change as expected :) *earlier than the current system time
A possibly relevant merge request was started @ https://invent.kde.org/plasma/plasma-workspace/-/merge_requests/5875
Can you share your timezone and ~/.config/knighttimerc? also, did you change any global theme related options or can you attach your kdeglobals file to this bug report too?
timezone info can be collected by running `timedatectl` command? if you feel uncomfortable posting this information in public here, can you send an email to me?
s/command?/command./
Git commit cca20d8287e433160468be40fab4a28494b22bb3 by Vlad Zahorodnii. Committed on 30/09/2025 at 12:44. Pushed by vladz into branch 'master'. kcms/lookandfeel: Add some debug messages M +8 -0 kcms/lookandfeel/kded/CMakeLists.txt M +9 -0 kcms/lookandfeel/kded/lookandfeelautoswitcher.cpp https://invent.kde.org/plasma/plasma-workspace/-/commit/cca20d8287e433160468be40fab4a28494b22bb3
A possibly relevant merge request was started @ https://invent.kde.org/plasma/plasma-workspace/-/merge_requests/5877
Created attachment 185400 [details] kdeglobals
(In reply to Vlad Zahorodnii from comment #11) > Can you share your timezone and ~/.config/knighttimerc? also, did you change > any global theme related options or can you attach your kdeglobals file to > this bug report too? knighttimerc: [ManualLocation] Latitude=45.154058011549154 Longitude=21.010521873235774 [Times] SunsetStart=20:04:00 TransitionDuration=2400 I set sunset to 20:04 after 20:04 has passed on that day. timezones: Local time: k 2025-09-30 16:46:27 CEST Universal time: k 2025-09-30 14:46:27 UTC RTC time: k 2025-09-30 14:46:27 Time zone: Europe/Budapest (CEST, +0200) System clock synchronized: yes NTP service: active RTC in local TZ: no
Git commit 83e5fb1a0510b5cc7418715d17bbfdc74d689aff by Vlad Zahorodnii. Committed on 30/09/2025 at 14:31. Pushed by vladz into branch 'Plasma/6.5'. kcms/lookandfeel: Add some debug messages (cherry picked from commit cca20d8287e433160468be40fab4a28494b22bb3) Co-authored-by: Vlad Zahorodnii <vlad.zahorodnii@kde.org> M +8 -0 kcms/lookandfeel/kded/CMakeLists.txt M +9 -0 kcms/lookandfeel/kded/lookandfeelautoswitcher.cpp https://invent.kde.org/plasma/plasma-workspace/-/commit/83e5fb1a0510b5cc7418715d17bbfdc74d689aff
(In reply to aronkvh from comment #17) > (In reply to Vlad Zahorodnii from comment #11) > > Can you share your timezone and ~/.config/knighttimerc? also, did you change > > any global theme related options or can you attach your kdeglobals file to > > this bug report too? > > knighttimerc: > [ManualLocation] > Latitude=45.154058011549154 > Longitude=21.010521873235774 > > [Times] > SunsetStart=20:04:00 > TransitionDuration=2400 > > I set sunset to 20:04 after 20:04 has passed on that day. > > timezones: > Local time: k 2025-09-30 16:46:27 CEST > Universal time: k 2025-09-30 14:46:27 UTC > RTC time: k 2025-09-30 14:46:27 > Time zone: Europe/Budapest (CEST, +0200) > System clock synchronized: yes > NTP service: active > RTC in local TZ: no Huh, [ManualLocation] is odd. According to knighttimerc, you're using automatic location mode, so changing the sunset time won't have any effect. I wonder whether KDE Linux has corrupted/outdated knighttime or plasma-workspace packages.
The problem is only with custom times, automatic location seems to work. (But when it's automatic you can't set a transition duration for night light, is that intended? Since the transition is only for night light, I think that KCM would be a better place for it)
(In reply to Vlad Zahorodnii from comment #19) > I wonder whether KDE Linux has corrupted/outdated knighttime or plasma-workspace packages. KDE Linux hadn't gotten any newer builds of KDE software since 2025-09-25 due to https://invent.kde.org/kde-linux/kde-linux/-/issues/371. So if there was a change that might have fixed this since then, KDE Linux users don't have it yet.
(In reply to aronkvh from comment #20) > The problem is only with custom times, automatic location seems to work. > > (But when it's automatic you can't set a transition duration for night > light, is that intended? Since the transition is only for night light, I > think that KCM would be a better place for it) Transition duration affects automatic theme switching too.