Bug 458821

Summary: Taskbar suddenly and randomly disappears and reappears
Product: [Plasma] plasmashell Reporter: myndstream
Component: generalAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED DOWNSTREAM    
Severity: normal CC: kde, nate
Priority: NOR    
Version First Reported In: 5.18.8   
Target Milestone: 1.0   
Platform: Debian stable   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description myndstream 2022-09-06 21:53:23 UTC
SUMMARY
In version 5.20.5-1 in Debian11 with Wayland, the taskbar suddenly and randomly disappears just to reappear around 2 seconds later. It seems like some plasmashell thing is getting restarted.

It always happens out of nowhere at different times as far as I can tell - I didn't run any upgrade or anything. No apps are closed, it's just that the bottom taskbar moves down and then reappears.

What could be causing this, which logs to check for what and how to prevent this?

STEPS TO REPRODUCE
1. Run Debian11/KDE
2. Wait / use the machine

OBSERVED RESULT
Taskbar suddenly disappears and reappears.


EXPECTED RESULT
The taskbar does not disappear and move down (it wiggles the windows).

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian 11
KDE Plasma Version:  5.20.5
KDE Frameworks Version: 5.78.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
Comment 1 myndstream 2022-09-08 15:22:59 UTC
Recently this occurred without the taskbar reappearing right after. Hence, I had time to open the task manager and search for plasma. Plasmashell was not running but only:

systemd->sddm->sddm-helper->startplasma-wayland->kwin_wayland->startplasma-waylandsession

Again, I didn't do anything that may have caused this at that point and running kstart5 plasmashell made it reappear.

The first output is:

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"
qt.qpa.wayland: Wayland does not support QWindow::requestActivate()
kf.plasma.core: requesting config for "Folder View" without a containment!
QObject::disconnect: Unexpected nullptr parameter
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/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!
Plasma Shell startup completed
Comment 2 Nate Graham 2022-09-09 04:14:23 UTC
Thank you for the bug report! It does indeed sound like Plasma is crashing and restarting. However Plasma 5.20.5 is no longer supported by KDE; supported versions are 5.24 and 5.25. Your distro is responsible for providing support for older versions of KDE software.

Please do one of the following:
- Upgrade to a supported version (perhaps using Debian Testing) and see if the issue is still relevant
- Report the issue to your distro
Comment 3 myndstream 2022-09-09 08:58:46 UTC
- I can only and will upgrade to a much newer version after Debian upgraded to Debian12. Once I did, I will try to check my submitted bugs and update them.  See https://unix.stackexchange.com/questions/584892/what-would-be-needed-by-debian-to-ship-newer-versions-of-the-kde-desktop-environ/584903

- Done: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1019433 (and only after I did this does it make sense to mark this issue as resolved)