SUMMARY

The panel completely freezes after some time. No visual updates. KRunner shortcut stops responding as well, but shows after ~30 seconds.

The rest of the desktop remains functional. But after some time all of the windows freeze too.

STEPS TO REPRODUCE
Didn't find any special steps.

OBSERVED RESULT

Completely frozen system.

EXPECTED RESULT



SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.82
Qt Version: 5.15

ADDITIONAL INFORMATION

Stacktrace I've got from plasmashell:

Tracepoint 1 at 0x7f59ab43a8ca
(gdb) b
backtrace    bookmark     break        break-range  bt           
(gdb) backtrace 
#0  0x00007f59ab43a8ca in __futex_abstimed_wait_common64 () at /usr/lib/libpthread.so.0
#1  0x00007f59ab434270 in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#2  0x00007f59ac47500c in QWaitCondition::wait(QMutex*, QDeadlineTimer) () at /usr/lib/libQt5Core.so.5
#3  0x00007f59ae122dd7 in  () at /usr/lib/libQt5Quick.so.5
#4  0x00007f59ae1912bf in QQuickWindow::event(QEvent*) () at /usr/lib/libQt5Quick.so.5
#5  0x00007f59ad310d62 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#6  0x00007f59ac65a00a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#7  0x00007f59aca20c29 in QPlatformWindow::windowEvent(QEvent*) () at /usr/lib/libQt5Gui.so.5
#8  0x00007f59ad318087 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#9  0x00007f59ac65a00a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#10 0x00007f59ac6b1fad in QTimerInfoList::activateTimers() () at /usr/lib/libQt5Core.so.5
#11 0x00007f59ac6b2872 in  () at /usr/lib/libQt5Core.so.5
#12 0x00007f59aa97b02c in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0
#13 0x00007f59aa9ceb59 in  () at /usr/lib/libglib-2.0.so.0
#14 0x00007f59aa978781 in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#15 0x00007f59ac6b2c36 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#16 0x00007f59ac65897c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#17 0x00007f59ac660ee4 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#18 0x000055cb9949220b in  ()
#19 0x00007f59abfe4b25 in __libc_start_main () at /usr/lib/libc.so.6
#20 0x000055cb9949233e in  ()
quit) 
A debugging session is active.