Login does not work after package updates

Help
, ,
1

Updated NEON today and after that I cannot log in using Wayland only with X. I can see the following error in the log:

This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.

Packages were upgraded:

Upgrade: linux-headers-generic-hwe-24.04:amd64 (6.8.0-49.49, 6.8.0-50.51), linux-generic-hwe-24.04:amd64 (6.8.0-49.49, 6.8.0-50.51), qt6-quick3d:amd64 (6.8.0-0zneon+24.04+noble+release+build8, 6.8.1-0zneon+24.04+noble+release+build11), breeze:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), plasma-runners-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), qt6-scxml:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), qml6-module-qt-labs-folderlistmodel:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), kdeplasma-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), qttranslations5-l10n:amd64 (5.15.14+p24.04+vrelease+git20240821.1253-0, 5.15.16+p24.04+vrelease+git20241207.0421-0), kf6-kguiaddons:amd64 (6.8.0-0zneon+24.04+noble+release+build7, 6.8.0-0zneon+24.04+noble+release+build8), skanlite:amd64 (24.08.3-0zneon+24.04+noble+release+build7, 24.12.0-0zneon+24.04+noble+release+build9), libqt6help6:amd64 (6.8.0-0zneon+24.04+noble+release+build20, 6.8.1-0zneon+24.04+noble+release+build28), qml6-module-qtquick-window:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), kf6-kirigami2:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), kinfocenter:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build10), linux-tools-common:amd64 (6.8.0-49.49, 6.8.0-50.51), kwayland-integration:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build11), neon-desktop:amd64 (4+p24.04+vrelease+git20241104.0535, 4+p24.04+vrelease+git20241126.0202), qt6-serialport:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build8), libqt6widgets6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), breeze5:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), qt6-translations:amd64 (6.8.0-0zneon+24.04+noble+release+build3, 6.8.1-0zneon+24.04+noble+release+build4), qt6-wayland:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build16), linux-headers-generic:amd64 (6.8.0-49.49, 6.8.0-50.51), kf6-plasma-framework:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build11), plasma-integration5:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), ark:amd64 (4:24.08.3-0zneon+24.04+noble+release+build7, 4:24.12.0-0zneon+24.04+noble+release+build8), kaccounts-providers:amd64 (4:24.08.3-0zneon+24.04+noble+release+build9, 4:24.12.0-0zneon+24.04+noble+release+build10), qml6-module-qt-labs-qmlmodels:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), plasma-workspace:amd64 (4:6.2.3-0zneon+24.04+noble+release+build17, 4:6.2.4-0zneon+24.04+noble+release+build18), plasma-widgets-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), libkdecorations2-6:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), qml6-module-qtqml-models:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), kpim6-libkgapi:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), qt5-image-formats-plugins:amd64 (5.15.14+p24.04+vrelease+git20240821.1030-0, 5.15.16+p24.04+vrelease+git20241207.0326-0), qml6-module-org-kde-qqc2breezestyle:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), kglobalacceld:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), plasma-systemmonitor:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), libqt5quickcontrols2-5:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0338-0), qt6-charts:amd64 (6.8.0-0zneon+24.04+noble+release+build6, 6.8.1-0zneon+24.04+noble+release+build9), drkonqi-pk-debug-installer:amd64 (0.1+p24.04+vrelease+git20241015.2349-0, 0.1+p24.04+vrelease+git20241210.0020-0), kwin-wayland:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build16), libqt6sql6-sqlite:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), libqt5xml5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), kf6-ki18n:amd64 (6.8.0-0zneon+24.04+noble+release+build7, 6.8.0-0zneon+24.04+noble+release+build8), print-manager:amd64 (5:6.2.3-0zneon+24.04+noble+release+build11, 5:6.2.4-0zneon+24.04+noble+release+build12), qml-module-qtquick-layouts:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), kscreen:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), qt6-tools:amd64 (6.8.0-0zneon+24.04+noble+release+build20, 6.8.1-0zneon+24.04+noble+release+build28), qt6-svg:amd64 (6.8.0-0zneon+24.04+noble+release+build10, 6.8.1-0zneon+24.04+noble+release+build14), kate6-data:amd64 (4:24.08.3-0zneon+24.04+noble+release+build8, 4:24.12.0-0zneon+24.04+noble+release+build9), qml-module-qtquick-window2:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), qt5-gtk-platformtheme:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), kf6-kirigami:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), libkpipewire6:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build11), kate:amd64 (4:24.08.3-0zneon+24.04+noble+release+build8, 4:24.12.0-0zneon+24.04+noble+release+build9), libkpipewirerecord6:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build11), libpam-kwallet5:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), libpam-kwallet6:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), libqt6network6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), qt6-imageformats:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), kf6-kwindowsystem:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), kdeconnect:amd64 (24.08.3-0zneon+24.04+noble+release+build14, 24.12.0-0zneon+24.04+noble+release+build16), kde-config-updates:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), qml-module-qt-labs-settings:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), qml6-module-org-kde-kaccounts:amd64 (4:24.08.3-0zneon+24.04+noble+release+build9, 4:24.12.0-0zneon+24.04+noble+release+build10), libqt5sql5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), qt6-webchannel:amd64 (6.8.0-0zneon+24.04+noble+release+build5, 6.8.1-0zneon+24.04+noble+release+build9), qt6-declarative:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), systemsettings:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build11), plasma-workspace-wallpapers:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), plasma-wallpapers-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), libqt5qml5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), xdg-desktop-portal-kde:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build8), okular-backends:amd64 (4:24.08.3-0zneon+24.04+noble+release+build13, 4:24.12.0-0zneon+24.04+noble+release+build14), gwenview:amd64 (4:24.08.3-0zneon+24.04+noble+release+build11, 4:24.12.0-0zneon+24.04+noble+release+build12), qml6-module-org-kde-ksysguard:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), libqt5test5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), qt6-base:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), qt6-gtk-platformtheme:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), libqt5x11extras5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0420-0), libqt6core6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), plasma-workspace-wayland:amd64 (4:6.2.3-0zneon+24.04+noble+release+build17, 4:6.2.4-0zneon+24.04+noble+release+build18), libqt6statemachine6:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), libqaccessibilityclient-qt6-0:amd64 (0.6.0-0zneon+24.04+noble+release+build2, 0.6.0-0zneon+24.04+noble+release+build3), kwrited:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), libokular6core1:amd64 (4:24.08.3-0zneon+24.04+noble+release+build13, 4:24.12.0-0zneon+24.04+noble+release+build14), qml-module-qtquick-controls2:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0338-0), krdp:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build8), libpowerdevilcore2:amd64 (4:6.2.3-0zneon+24.04+noble+release+build12, 4:6.2.4-0zneon+24.04+noble+release+build15), layer-shell-qt:amd64 (6.2.3-0zneon+24.04+noble+release+build11, 6.2.4-0zneon+24.04+noble+release+build13), libinput10:amd64 (1.25.0-1ubuntu2, 1.26.2-1+24.04+noble+release+build1), ksystemstats:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build8), kio-extras:amd64 (4:24.08.3-0zneon+24.04+noble+release+build10, 4:24.12.0-0zneon+24.04+noble+release+build12), libqt6widgets6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), kde-style-breeze5:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), plasma-discover-common:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), qml-module-qtquick-localstorage:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), kde-config-gtk-style:amd64 (4:6.2.3-0zneon+24.04+noble+release+build10, 4:6.2.4-0zneon+24.04+noble+release+build11), kf6-kiconthemes:amd64 (6.8.0-0zneon+24.04+noble+release+build10, 6.8.0-0zneon+24.04+noble+release+build11), kio-gdrive:amd64 (24.08.3-0zneon+24.04+noble+release+build11, 24.12.0-0zneon+24.04+noble+release+build12), qml6-module-qt-labs-settings:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), powerdevil:amd64 (4:6.2.3-0zneon+24.04+noble+release+build12, 4:6.2.4-0zneon+24.04+noble+release+build15), qml6-module-qtquick-particles:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), dolphin-plugins:amd64 (4:24.08.3-0zneon+24.04+noble+release+build8, 4:24.12.0-0zneon+24.04+noble+release+build9), libqt5xmlpatterns5:amd64 (5.15.14+p24.04+vrelease+git20240821.1112-0, 5.15.16+p24.04+vrelease+git20241207.0336-0), kscreenlocker:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build15), python3-pyqt5:amd64 (5.15.11+dfsg-1+24.04+noble+release+build3, 5.15.11+dfsg-1+24.04+noble+release+build5), drkonqi:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build13), libpam-kwallet-common:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), libqt5quick5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), qt6-webview:amd64 (6.8.0-0zneon+24.04+noble+release+build5, 6.8.1-0zneon+24.04+noble+release+build9), libqt6dbus6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), kactivitymanagerd:amd64 (6.2.3-0zneon+24.04+noble+release+build11, 6.2.4-0zneon+24.04+noble+release+build13), qtwayland5:amd64 (5.15.14+p24.04+vrelease+git20240821.1105-0, 5.15.16+p24.04+vrelease+git20241207.0330-0), libqt5waylandcompositor5:amd64 (5.15.14+p24.04+vrelease+git20240821.1105-0, 5.15.16+p24.04+vrelease+git20241207.0330-0), linux-generic:amd64 (6.8.0-49.49, 6.8.0-50.51), qml-module-qtmultimedia:amd64 (5.15.14+p24.04+vrelease+git20240821.1104-0, 5.15.16+p24.04+vrelease+git20241207.0340-0), libkexiv2:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), plasma-browser-integration:amd64 (6.2.3-0zneon+24.04+noble+release+build11, 6.2.4-0zneon+24.04+noble+release+build14), dolphin:amd64 (4:24.08.3-0zneon+24.04+noble+release+build10, 4:24.12.0-0zneon+24.04+noble+release+build11), libkf6screen-bin:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), kde-config-gtk-style-preview:amd64 (4:6.2.3-0zneon+24.04+noble+release+build10, 4:6.2.4-0zneon+24.04+noble+release+build11), flatpak-kcm:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build9), libqt5multimediaquick5:amd64 (5.15.14+p24.04+vrelease+git20240821.1104-0, 5.15.16+p24.04+vrelease+git20241207.0340-0), qml6-module-qt-labs-platform:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), qt6-image-formats-plugins:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), qml6-module-qtmultimedia:amd64 (6.8.0-0zneon+24.04+noble+release+build21, 6.8.1-0zneon+24.04+noble+release+build26), kwin-x11:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build16), firefox:amd64 (133.0~build2, 133.0.3~build1), qml6-module-org-kde-kconfig:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), qt6-5compat:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build7), plasma-wayland-protocols:amd64 (1.14.0-0zneon+24.04+noble+release+build2, 1.15.0-0zneon+24.04+noble+release+build3), kwin-style-breeze:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), kf6-baloowidgets:amd64 (4:24.08.3-0zneon+24.04+noble+release+build6, 4:24.12.0-0zneon+24.04+noble+release+build7), qml6-module-qtwebengine:amd64 (6.8.0-0zneon+24.04+noble+release+build7, 6.8.1-0zneon+24.04+noble+release+build10), libqt5gui5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), kde-nomodeset:amd64 (0.1+p24.04+vrelease+git20241108.0400-0, 0.1+p24.04+vrelease+git20241203.0023-0), libqt5multimedia5:amd64 (5.15.14+p24.04+vrelease+git20240821.1104-0, 5.15.16+p24.04+vrelease+git20241207.0340-0), plasma-discover-backend-snap:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), libqt6gui6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), plasma-dataengines-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), keditbookmarks:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), qt6-multimedia:amd64 (6.8.0-0zneon+24.04+noble+release+build21, 6.8.1-0zneon+24.04+noble+release+build26), ksshaskpass:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), plasma-integration:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), plasma-disks:amd64 (6.2.3-0zneon+24.04+noble+release+build9, 6.2.4-0zneon+24.04+noble+release+build10), kde-config-plymouth:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), kf6-kio:amd64 (6.8.0-0zneon+24.04+noble+release+build12, 6.8.0-0zneon+24.04+noble+release+build13), qml6-module-qtquick-dialogs:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), libqt5printsupport5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), qt6-translations-l10n:amd64 (6.8.0-0zneon+24.04+noble+release+build3, 6.8.1-0zneon+24.04+noble+release+build4), libqt6xml6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), kdeplasma-addons-data:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), plymouth-theme-breeze:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build10), sddm-theme-breeze:amd64 (4:6.2.3-0zneon+24.04+noble+release+build17, 4:6.2.4-0zneon+24.04+noble+release+build18), kdegraphics-thumbnailers:amd64 (4:24.08.3-0zneon+24.04+noble+release+build6, 4:24.12.0-0zneon+24.04+noble+release+build7), konsole:amd64 (4:24.08.3-0zneon+24.04+noble+release+build8, 4:24.12.0-0zneon+24.04+noble+release+build9), libkdecorations2private11:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), kamera:amd64 (4:24.08.3-0zneon+24.04+noble+release+build6, 4:24.12.0-0zneon+24.04+noble+release+build7), qt6-virtualkeyboard:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), kdialog:amd64 (4:24.08.3-0zneon+24.04+noble+release+build6, 4:24.12.0-0zneon+24.04+noble+release+build7), okular:amd64 (4:24.08.3-0zneon+24.04+noble+release+build13, 4:24.12.0-0zneon+24.04+noble+release+build14), milou:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), qml6-module-qtquick-layouts:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), libqt5texttospeech5:amd64 (5.15.14+p24.04+vrelease+git20240821.1129-0, 5.15.16+p24.04+vrelease+git20241207.0331-0), plasma-welcome:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build10), libkdcraw:amd64 (24.08.3-0zneon+24.04+noble+release+build5, 24.12.0-0zneon+24.04+noble+release+build6), kwayland:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), libkf6screen8:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), kgamma:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), kf6-plasma5support:amd64 (6.2.3-0zneon+24.04+noble+release+build16, 6.2.4-0zneon+24.04+noble+release+build17), libqt5widgets5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), kde-config-sddm:amd64 (4:6.2.3-0zneon+24.04+noble+release+build10, 4:6.2.4-0zneon+24.04+noble+release+build11), libqmobipocket6-2:amd64 (4:24.08.3-0zneon+24.04+noble+release+build6, 4:24.12.0-0zneon+24.04+noble+release+build7), qml6-module-qtquick:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), libqt6xml6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), linux-image-generic:amd64 (6.8.0-49.49, 6.8.0-50.51), qml6-module-org-kde-qqc2desktopstyle:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), kaccounts-integration:amd64 (4:24.08.3-0zneon+24.04+noble+release+build9, 4:24.12.0-0zneon+24.04+noble+release+build10), plasma-thunderbolt:amd64 (6.2.3-0zneon+24.04+noble+release+build9, 6.2.4-0zneon+24.04+noble+release+build12), qml-module-qtgraphicaleffects:amd64 (5.15.14+p24.04+vrelease+git20240821.1104-0, 5.15.16+p24.04+vrelease+git20241207.0319-0), plasma-vault:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build10), qml-module-qt-labs-folderlistmodel:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), kde-inotify-survey:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), plasma5support:amd64 (6.2.3-0zneon+24.04+noble+release+build16, 6.2.4-0zneon+24.04+noble+release+build17), qt6-shadertools:amd64 (6.8.0-0zneon+24.04+noble+release+build6, 6.8.1-0zneon+24.04+noble+release+build10), linux-image-generic-hwe-24.04:amd64 (6.8.0-49.49, 6.8.0-50.51), kf6-frameworkintegration:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), libqt5svg5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0343-0), kgamma5:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), sddm:amd64 (0.21.0-0zneon+24.04+noble+release+build3, 0.21.0-0zneon+24.04+noble+release+build5), kf6-kactivities:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build11), qml6-module-qtqml:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), oxygen-sounds:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), kf6-attica:amd64 (6.8.0-0zneon+24.04+noble+release+build7, 6.8.0-0zneon+24.04+noble+release+build10), kde-style-breeze:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), qml6-module-qt5compat-graphicaleffects:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build7), breeze-cursor-theme:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build13), kmenuedit:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), libqt5dbus5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), libqt6svg6:amd64 (6.8.0-0zneon+24.04+noble+release+build10, 6.8.1-0zneon+24.04+noble+release+build14), plasma-nm:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), plasma-pa:amd64 (4:6.2.3-0zneon+24.04+noble+release+build9, 4:6.2.4-0zneon+24.04+noble+release+build10), libqt5network5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), plasma-calendar-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), skanpage:amd64 (24.08.3-0zneon+24.04+noble+release+build7, 24.12.0-0zneon+24.04+noble+release+build8), libqt5quicktemplates2-5:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0338-0), qml6-module-org-kde-kirigami2:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), libdolphinvcs6:amd64 (4:24.08.3-0zneon+24.04+noble+release+build10, 4:24.12.0-0zneon+24.04+noble+release+build11), qml-module-qtqml-models2:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), qml-module-qtquick-privatewidgets:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0336-0), qtspeech5-speechd-plugin:amd64 (5.15.14+p24.04+vrelease+git20240821.1129-0, 5.15.16+p24.04+vrelease+git20241207.0331-0), libqt5opengl5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), libqt6core6:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), qml6-module-org-kde-kcm:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), breeze-gtk-theme:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build9), qt6-sensors:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), liblayershellqtinterface6:amd64 (6.2.3-0zneon+24.04+noble+release+build11, 6.2.4-0zneon+24.04+noble+release+build13), ocean-sound-theme:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build8), khelpcenter:amd64 (4:24.08.3-0zneon+24.04+noble+release+build7, 4:24.12.0-0zneon+24.04+noble+release+build8), kde-spectacle:amd64 (24.08.3-0zneon+24.04+noble+release+build14, 24.12.0-0zneon+24.04+noble+release+build15), qml6-module-org-kde-kquickcontrols:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), qt6-positioning:amd64 (6.8.0-0zneon+24.04+noble+release+build13, 6.8.1-0zneon+24.04+noble+release+build16), libqt6dbus6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), kf6-kxmlgui:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), plasma-activities-stats:amd64 (6.2.3-0zneon+24.04+noble+release+build11, 6.2.4-0zneon+24.04+noble+release+build12), neon-settings-2:amd64 (0.5+p24.04+vrelease+git20241101.1152, 0.5+p24.04+vrelease+git20241211.1400), qt6-quicktimeline:amd64 (6.8.0-0zneon+24.04+noble+release+build3, 6.8.1-0zneon+24.04+noble+release+build5), qml-module-qtquick-templates2:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0338-0), plasma-discover:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), plasma-firewall:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build8), qt6-speech:amd64 (6.8.0-0zneon+24.04+noble+release+build6, 6.8.1-0zneon+24.04+noble+release+build9), libqt5sql5-sqlite:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), libksane:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), libqt5qmlmodels5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), libplasma6:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build11), plasma-activities:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build11), polkit-kde-agent-1:amd64 (4:6.2.3-0zneon+24.04+noble+release+build10, 4:6.2.4-0zneon+24.04+noble+release+build11), kf6-kdeclarative:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), konsole-kpart:amd64 (4:24.08.3-0zneon+24.04+noble+release+build8, 4:24.12.0-0zneon+24.04+noble+release+build9), qml-module-qtquick-xmllistmodel:amd64 (5.15.14+p24.04+vrelease+git20240821.1112-0, 5.15.16+p24.04+vrelease+git20241207.0336-0), qml6-module-org-kde-kquickcontrolsaddons:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), libqt5designer5:amd64 (5.15.14+p24.04+vrelease+git20240821.1232-0, 5.15.16+p24.04+vrelease+git20241207.0235-0), qml-module-qtquick2:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), kde-cli-tools-data:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build10), libqt5feedback5:amd64 (5.0+p24.04+vrelease+git20240821.1253-0, 5.0+p24.04+vrelease+git20241207.0422-0), qml6-module-org-kde-pipewire:amd64 (6.2.3-0zneon+24.04+noble+release+build7, 6.2.4-0zneon+24.04+noble+release+build11), ffmpegthumbs:amd64 (4:24.08.3-0zneon+24.04+noble+release+build7, 4:24.12.0-0zneon+24.04+noble+release+build8), qml6-module-qtquick-virtualkeyboard:amd64 (6.8.0-0zneon+24.04+noble+release+build4, 6.8.1-0zneon+24.04+noble+release+build6), qt6-qpa-plugins:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), libksysguard:amd64 (4:6.2.3-0zneon+24.04+noble+release+build7, 4:6.2.4-0zneon+24.04+noble+release+build8), qml-module-qtquick-dialogs:amd64 (5.15.14+p24.04+vrelease+git20240821.1118-0, 5.15.16+p24.04+vrelease+git20241207.0336-0), kwin-addons:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build17), qml6-module-qtquick-templates:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), neon-essentials-desktop:amd64 (0.5+p24.04+vrelease+git20241101.1152, 0.5+p24.04+vrelease+git20241211.1400), qt6-webengine:amd64 (6.8.0-0zneon+24.04+noble+release+build7, 6.8.1-0zneon+24.04+noble+release+build10), plasma-framework:amd64 (6.2.3-0zneon+24.04+noble+release+build10, 6.2.4-0zneon+24.04+noble+release+build11), libqt5qmlworkerscript5:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), distro-release-notifier:amd64 (20240919+p24.04+vrelease+git20241113.0055-0, 20240919+p24.04+vrelease+git20241203.0023-0), libqt6printsupport6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), bluedevil:amd64 (4:6.2.3-0zneon+24.04+noble+release+build11, 4:6.2.4-0zneon+24.04+noble+release+build12), kf6-qqc2-desktop-style:amd64 (6.8.0-0zneon+24.04+noble+release+build9, 6.8.0-0zneon+24.04+noble+release+build10), qml6-module-qtquick-controls:amd64 (6.8.0-0zneon+24.04+noble+release+build15, 6.8.1-0zneon+24.04+noble+release+build31), libksanecore:amd64 (24.08.3-0zneon+24.04+noble+release+build5, 24.12.0-0zneon+24.04+noble+release+build6), kwin-data:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build16), grub-theme-breeze:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), libqt5waylandclient5:amd64 (5.15.14+p24.04+vrelease+git20240821.1105-0, 5.15.16+p24.04+vrelease+git20241207.0330-0), libqt6keychain1:amd64 (0.14.3-0zneon+24.04+noble+release+build3, 0.14.3-0zneon+24.04+noble+release+build5), sddm-theme-maya:amd64 (0.21.0-0zneon+24.04+noble+release+build3, 0.21.0-0zneon+24.04+noble+release+build5), intel-microcode:amd64 (3.20240910.0ubuntu0.24.04.1, 3.20241112.0ubuntu0.24.04.1), powerdevil-data:amd64 (4:6.2.3-0zneon+24.04+noble+release+build12, 4:6.2.4-0zneon+24.04+noble+release+build15), plasma-desktop:amd64 (4:6.2.3-0zneon+24.04+noble+release+build13, 4:6.2.4-0zneon+24.04+noble+release+build14), libqt5core5t64:amd64 (5.15.14+p24.04+vrelease+git20240821.0907-0, 5.15.16+p24.04+vrelease+git20241207.0024-0), kde-cli-tools:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build10), libqt5help5:amd64 (5.15.14+p24.04+vrelease+git20240821.1232-0, 5.15.16+p24.04+vrelease+git20241207.0235-0), plasma-discover-backend-flatpak:amd64 (6.2.3-0zneon+24.04+noble+release+build8, 6.2.4-0zneon+24.04+noble+release+build11), qml-module-qtqml:amd64 (5.15.14+p24.04+vrelease+git20240821.1031-0, 5.15.16+p24.04+vrelease+git20241207.0159-0), kf6-kirigami-addons:amd64 (1:1.5.0-0zneon+24.04+noble+release+build7, 1:1.6.0-0zneon+24.04+noble+release+build9), qml-module-qtfeedback:amd64 (5.0+p24.04+vrelease+git20240821.1253-0, 5.0+p24.04+vrelease+git20241207.0422-0), libinput-bin:amd64 (1.25.0-1ubuntu2, 1.26.2-1+24.04+noble+release+build1), kio-admin:amd64 (24.08.3-0zneon+24.04+noble+release+build6, 24.12.0-0zneon+24.04+noble+release+build7), libqt6gui6t64:amd64 (6.8.0-0zneon+24.04+noble+release+build17, 6.8.1-0zneon+24.04+noble+release+build38), libkf6screendpms8:amd64 (4:6.2.3-0zneon+24.04+noble+release+build8, 4:6.2.4-0zneon+24.04+noble+release+build9), kwin-common:amd64 (4:6.2.3-0zneon+24.04+noble+release+build14, 4:6.2.4-0zneon+24.04+noble+release+build16), linux-libc-dev:amd64 (6.8.0-49.49, 6.8.0-50.51)

1 Like
2

full upgrade may be helpful
please try

sudo apt update
sudo apt full-upgrade

from terminal

3

Thx for the quick reaction, been there, done that, nothing to upgrade at this moment.

sudo apt full-upgrade
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Starting pkgProblemResolver with broken count: 0
Starting 2 pkgProblemResolver with broken count: 0
Done
Entering ResolveByKeep
Calculating upgrade... Done
The following upgrades have been deferred due to phasing:
  gir1.2-packagekitglib-1.0 libegl-mesa0 libgbm1 libgl1-mesa-dri libglapi-mesa libglx-mesa0 libnet-ip-perl libpackagekit-glib2-18 libudisks2-0 libxatracker2 mesa-va-drivers
  mesa-vdpau-drivers mesa-vulkan-drivers packagekit packagekit-tools python3-apport python3-problem-report thermald udisks2
0 upgraded, 0 newly installed, 0 to remove and 19 not upgraded.
4

seems qt platform should be re installing
could you try sudo apt --fix-broken install

5 
 sudo apt --fix-broken install
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Starting pkgProblemResolver with broken count: 0
Starting 2 pkgProblemResolver with broken count: 0
Done
0 upgraded, 0 newly installed, 0 to remove and 19 not upgraded.
6

sudo apt autoremove
then sudo apt update
and than pkcon update

7

Packages were updated, rebooted, same old with Wayland.

8

Updated my other machine, same result. The following packages were updated: ark/noble 4:24.12.0-0zneon+24.04+noble+release+build8 amd64 [upgradable from: 4: - Pastebin.com

9

Which kernel are you using? I had a similar problem and using the older one works

10

I did not have the exact problem described on the first post but there was a time also after an update that I could not relogon when Kscreenlocker would not accept my user password. Maybe this is worth a try:

chmod 4755 /sbin/unix_chkpwd

11

This was a kernel update that happened the same time when Plasma stopped working. Checked and the issue still occurs with the older kernel version.

12

Thanks for the reply, most likely this is not the fix for my issue.

13

More errors from the log when log in fails on Wayland

08:53:49 systemd-cryptse: Failed to deactivate 'luks-88325a3e-11d2-4688-b745-68617bd71a74': Device or resource busy
08:53:46 resolvconf: Failed to revert interface configuration: Unit dbus-org.freedesktop.network1.service not found.
08:53:46 kernel: cs35l41-hda i2c-CSC3551:00-cs35l41-hda.0: DSP1: Failed to read 256 bytes from 2800608: -16
08:52:13 systemd: Failed to start plasma-xembedsniproxy.service - Handle legacy xembed system tray icons.
08:52:13 org_kde_powerde: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:13 systemd: Failed to start plasma-polkit-agent.service - KDE PolicyKit Authentication Agent.
08:52:13 polkit-kde-auth: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:13 systemd: Failed to start plasma-powerdevil.service - Powerdevil.
08:52:13 org_kde_powerde: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:13 systemd: Failed to start plasma-polkit-agent.service - KDE PolicyKit Authentication Agent.
08:52:13 polkit-kde-auth: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:13 systemd: Failed to start plasma-plasmashell.service - KDE Plasma Workspace.
08:52:12 plasmashell: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-powerdevil.service - Powerdevil.
08:52:12 org_kde_powerde: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-polkit-agent.service - KDE PolicyKit Authentication Agent.
08:52:12 polkit-kde-auth: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-plasmashell.service - KDE Plasma Workspace.
08:52:12 plasmashell: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-powerdevil.service - Powerdevil.
08:52:12 org_kde_powerde: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-polkit-agent.service - KDE PolicyKit Authentication Agent.
08:52:12 polkit-kde-auth: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 guake: Can't create a GtkStyleContext without a display connection
08:52:12 systemd: Failed to start plasma-plasmashell.service - KDE Plasma Workspace.
08:52:12 plasmashell: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-polkit-agent.service - KDE PolicyKit Authentication Agent.
08:52:12 polkit-kde-auth: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-kcminit-phase1.service - KDE Configuration Module Initialization (Phase 1).
08:52:12 ksmserver: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-kded6.service - KDE Daemon 6.
08:52:12 kded6: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start plasma-ksplash.service - Splash screen shown during boot.
08:52:12 ksplashqml: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: minimalegl, eglfs, minimal, vnc, offscreen, xcb, wayland, wayland-egl, linuxfb, vkkhrdisplay.
08:52:12 systemd: Failed to start xdg-desktop-portal-gtk.service - Portal service (GTK/GNOME implementation).
08:52:00 (uetoothd): sap-server: Operation not permitted (1)
08:51:59 kernel: amd-pmf AMDI0102:00: ta invoke cmd init failed err: 60005
14

Okay so I was YOLOd, it it worked :open_mouth: Downgraded KWIN and dependencies to their original versions.

sudo apt install kwin-wayland=4:6.2.3-0zneon+24.04+noble+release+build14 kwin-common=4:6.2.3-0zneon+24.04+noble+release+build14 kwin-x11=4:6.2.3-0zneon+24.04+noble+release+build14 kwin-data=4:6.2.3-0zneon+24.04+noble+release+build14
15

Worked on my second machine as well

dpkg: warning: downgrading kwin-x11 from 4:6.2.4-0zneon+24.04+noble+release+build16 to 4:6.2.3-0zneon+24.04+noble+release+build14
(Reading database ... 289569 files and directories currently installed.)
Preparing to unpack .../kwin-x11_4%3a6.2.3-0zneon+24.04+noble+release+build14_amd64.deb ...
Unpacking kwin-x11 (4:6.2.3-0zneon+24.04+noble+release+build14) over (4:6.2.4-0zneon+24.04+noble+release+build16) ...
dpkg: warning: downgrading kwin-wayland from 4:6.2.4-0zneon+24.04+noble+release+build16 to 4:6.2.3-0zneon+24.04+noble+release+build14
Preparing to unpack .../kwin-wayland_4%3a6.2.3-0zneon+24.04+noble+release+build14_amd64.deb ...
Unpacking kwin-wayland (4:6.2.3-0zneon+24.04+noble+release+build14) over (4:6.2.4-0zneon+24.04+noble+release+build16) ...
dpkg: warning: downgrading kwin-common from 4:6.2.4-0zneon+24.04+noble+release+build16 to 4:6.2.3-0zneon+24.04+noble+release+build14
Preparing to unpack .../kwin-common_4%3a6.2.3-0zneon+24.04+noble+release+build14_amd64.deb ...
Unpacking kwin-common (4:6.2.3-0zneon+24.04+noble+release+build14) over (4:6.2.4-0zneon+24.04+noble+release+build16) ...
dpkg: warning: downgrading kwin-data from 4:6.2.4-0zneon+24.04+noble+release+build16 to 4:6.2.3-0zneon+24.04+noble+release+build14
Preparing to unpack .../kwin-data_4%3a6.2.3-0zneon+24.04+noble+release+build14_all.deb ...
Unpacking kwin-data (4:6.2.3-0zneon+24.04+noble+release+build14) over (4:6.2.4-0zneon+24.04+noble+release+build16) ...
Setting up kwin-data (4:6.2.3-0zneon+24.04+noble+release+build14) ...
Setting up kwin-common (4:6.2.3-0zneon+24.04+noble+release+build14) ...
Setting up kwin-wayland (4:6.2.3-0zneon+24.04+noble+release+build14) ...
16

Reported this as a bug since this is still happening: 498137 – Log in on Wayland fails with return to the login screen

17

Now I cannot downgrade anymore so back to square one… does this log entry helps with debugging?

cat ~/.local/share/sddm/wayland-session.log
Error: could not determine $DISPLAY.
Error: Can not contact kdeinit5!
org.kde.startup: “kdeinit5_shutdown” QList() exited with code 255
startplasma-wayland: Shutting down…
startplasmacompositor: Shutting down…
startplasmacompositor: Done.

18

Run
sudo pkcon install libdecor-0-0 libsdl2-2.0-0 plasma-desktop plasma-desktop-data --allow-reinstall

but finally what solved my problem is removing the AMD GPU driver… sudo amdgpu-install --uninstall