I upgraded from Debian 10 to 11. After completing the upgrade – which had problems due to lack of disk space (there should have been enough), some rkhunter config and unattended-upgr blocking konsole commands – I rebooted.
The first strange thing was that the initial boot screen asking for the grub password was red and looked a bit strange instead of blue but quickly changed back to the blue one. The second problem was that after logging in I only have a black screen (with some windows on top). This is because plasmashell isn't running (the only thing that runs is startplasma-x11) so I started it with kstart5 plasmashell. However, it crashes right after it seems to have fully loaded (with the desktop and the task bar showing). How to solve this? The full output is:
Omitting both --window and --windowclass arguments is not recommended kf.coreaddons: Expected JSON property "X-Plasma-ContainmentCategories" to be a string list. Treating it as a list with a single entry: "panel" org.kde.plasma.desktop.defaultPanel kf.coreaddons: Expected JSON property "X-Plasma-ContainmentCategories" to be a string list. Treating it as a list with a single entry: "panel" org.kde.plasma.desktop.appmenubar kf.coreaddons: Expected JSON property "X-Plasma-ContainmentCategories" to be a string list. Treating it as a list with a single entry: "panel" org.kde.plasma.desktop.emptyPanel kf.plasma.quick: Applet preload policy set to 1 Cyclic dependency detected between "file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/styles/org.kde.desktop.plasma/Units.qml" and "file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/kirigami.2/styles/org.kde.desktop.plasma/Units.qml" qt.svg: <input>:406:376: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:407:130: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:408:130: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:408:393: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:409:130: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:410:129: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:411:129: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:412:129: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:413:129: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:413:379: Could not add child element to parent element because the types are incorrect. qt.svg: <input>:413:631: Could not add child element to parent element because the types are incorrect. trying to show an empty dialog file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" trying to show an empty dialog file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" libpng warning: iCCP: known incorrect sRGB profile kf.coreaddons: KDirWatch: "/usr/share/desktop-base/homeworld-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/futureprototype-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/futureprototype-theme/wallpaper-withlogo" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/joy-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/joy-inksplat-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/joy-theme/lockscreen" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/lines-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/lines-theme/lockscreen" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/moonlight-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/moonlight-theme/lockscreen" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/wallpapers/Next" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/softwaves-theme/wallpaper" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/softwaves-theme/lockscreen" is a directory. Use addDir! kf.coreaddons: KDirWatch: "/usr/share/desktop-base/spacefun-theme/wallpaper" is a directory. Use addDir! libpng warning: iCCP: known incorrect sRGB profile Plasma Shell startup completed qml: disabling redshift qml: renderModeString: qml: disabling redshift qml: onLoaded Connecting to deprecated signal QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString) file:///usr/share/plasma/plasmoids/org.kde.panel/contents/ui/main.qml:30:1: QML DropArea (parent or ancestor of QQuickLayoutAttached): Binding loop detected for property "minimumWidth" Both point size and pixel size set. Using pixel size. Both point size and pixel size set. Using pixel size. Both point size and pixel size set. Using pixel size. trying to show an empty dialog trying to show an empty dialog trying to show an empty dialog Cyclic dependency detected between "file:///usr/share/plasma/plasmoids/org.kde.plasma.notifications/contents/ui/global/Globals.qml" and "file:///usr/share/plasma/plasmoids/org.kde.plasma.notifications/contents/ui/NotificationHeader.qml" file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/plasma/extras/PlasmoidHeading.qml:56:5: Unable to assign [undefined] to int Plasma Shell startup completed Plasma Shell startup completed trying to show an empty dialog file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/views/Desktop.qml:146:19: QML Loader: Binding loop detected for property "height" KAStatsFavoritesModel::setFavorites is ignored Entry is not valid "applications:seahorse.desktop" QSharedPointer(0x563b9bdb07d0) Entry is not valid "applications:seahorse.desktop" QSharedPointer(0x563b9bd267e0) file:///usr/share/plasma/plasmoids/org.kde.plasma.kickoff/contents/ui/FullRepresentation.qml:356: ReferenceError: headerSeparator is not defined trying to show an empty dialog qml: clearing connected sources, stop source was: killall redshift; redshift -x qml: enabling redshift with command: redshift [...] libpng warning: iCCP: known incorrect sRGB profile libpng warning: known incorrect sRGB profile libpng warning: profile matches sRGB but writing iCCP instead file:///home/username/.local/share/plasma/plasmoids/org.kde.plasma.eventcalendar/contents/ui/TimerView.qml:31:13: QML ToolButton: Detected anchors on an item that is managed by a layout. This is undefined behavior; use Layout.alignment instead. file:///home/username/.local/share/plasma/plasmoids/org.kde.plasma.eventcalendar/contents/ui/TimerView.qml:87:13: QML ColumnLayout: Detected anchors on an item that is managed by a layout. This is undefined behavior; use Layout.alignment instead.