https://bugs.kde.org/show_bug.cgi?id=527720
--- Comment #2 from dmrx921 <[email protected]> --- Thanks for the detailed analysis, this is very useful. I can confirm the same symptom on EndeavourOS with Plasma 6.8.1 (Wayland), kwin 6.8.1-2, and the same QObject::disconnect: Unexpected nullptr parameter error followed by the stop-sigterm timeout. However, in my case CUPS is not installed at all (systemctl status cups.service returns "Unit cups.service could not be found"). So the Printers applet cannot be the cause here. My running services that could be involved are: - KDE Connect ([email protected]) — active - bluetooth.service — active (adapter off, but daemon running) - NetworkManager.service — active - pipewire.service / wireplumber.service — active Given your findings, it seems the underlying issue is generic: any applet that tries to reconnect to a service which is stopped before the user session ends will block plasmashell's shutdown. In my case the main suspect is KDE Connect (and possibly PipeWire/Bluetooth). I haven't applied any workaround yet. I'll test the ordering approach (user session stopping before the services it depends on) and report back. El sáb, 24 oct 2026 a las 18:05, Franck Maurice (<[email protected]>) escribió: > https://bugs.kde.org/show_bug.cgi?id=527720 > > Franck Maurice <[email protected]> changed: > > What |Removed |Added > > ---------------------------------------------------------------------------- > CC| |[email protected] > > --- Comment #1 from Franck Maurice <[email protected]> --- > I can reproduce this 100% of the time on EndeavourOS with Plasma 6.8.1 > (Wayland), and I think I found the cause: the system tray Printers applet > (print-manager). > > VERSIONS > - plasma-workspace / print-manager 6.8.1, kwin 6.8.1-2 > - cups 2.4.20, qt6-base 6.12.0 > - Kernel 7.2.11-arch1-1, SDDM 0.21.0 > > WHAT HAPPENS > When you reboot, systemd stops cups.service and the user session at the > same > time. CUPS goes down first, and plasmashell immediately logs, in a loop: > > plasmashell: IPP_INTERNAL_ERROR: clearing cookies and reconnecting > plasmashell: Failed to reconnect Invalid argument > (repeated) > plasmashell: QObject::disconnect: Unexpected nullptr parameter > > Then plasmashell stops responding to SIGTERM: > > plasma-plasmashell.service: State 'stop-sigterm' timed out. Killing. > plasma-plasmashell.service: Failed with result 'timeout'. > > The console shows "A stop job is running for User Manager for UID 1000". > > ISOLATION > - Plain image wallpaper: still hangs (I ruled out the wallpaper plugins). > - Printers entry disabled in System Tray settings: no hang on any reboot. > - Printers applet re-enabled, plus a drop-in that makes the user session > stop > before CUPS: > /etc/systemd/system/[email protected]/after-cups.conf > [Unit] > After=cups.service cups.socket > Two reboots in a row: clean, plasmashell exits in under a second, no > IPP_INTERNAL_ERROR. > > So the applet's (or libkcups') reconnect logic seems to block plasmashell's > shutdown when the CUPS server goes away. Maybe this report should be moved > to > print-manager / applet. > ~ > > -- > You are receiving this mail because: > You reported the bug. -- You are receiving this mail because: You are watching all bug changes.
