Occasionally selecting another workspace using the Desktop Grid causes Plasma to crash. This causes flashing and program windows are rearranged into different workspaces. Any window that was set to show "only in this activity" is also reset to show on all activities. This happens on average 2-3 times per day. Issue has been present at least since I started using KDE with Kubuntu 19.10 last year. I tend to open the Desktop Grid via a screen corner, if that matters, but it doesn't crash when the Grid is first opened, but rather when a window or workspace on the grid is clicked.


STEPS TO REPRODUCE
1. Open desktop grid via hot corner.
2. Select a window to open.

OBSERVED RESULT
Sometimes Plasma crashes, causing the windows to be rearranged to different workspaces. 

EXPECTED RESULT
No crash, window is selected and brought to the front. 


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu 20.04
(available in About System)
KDE Plasma Version: Plasma Version 5.18.5
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
Running an Intel Core i7-8700K with UHD Graphics 630.

Backtrace:

Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fa0aac62080 (LWP 18746))]

Thread 14 (Thread 0x7fa0a3fff700 (LWP 19257)):
#0  0x00007fa0b1a15a66 in __ppoll (fds=0x7fa09801a678, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:44
#1  0x00007fa0b03e84a9 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa0b03e9a14 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01cb785 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0aef1f1a9 in ?? () from /lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 13 (Thread 0x7f9fda35e700 (LWP 18779)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb723f00c4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb723f0070, cond=0x55bb723f0098) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb723f0098, mutex=0x55bb723f0070) at pthread_cond_wait.c:638
#3  0x00007fa0b01d2b0f in QWaitCondition::wait(QMutex*, QDeadlineTimer) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01d2c01 in QWaitCondition::wait(QMutex*, unsigned long) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0af290109 in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fa0af2903ad in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7f9fe928c700 (LWP 18770)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb72239aa4) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb72239a50, cond=0x55bb72239a78) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb72239a78, mutex=0x55bb72239a50) at pthread_cond_wait.c:638
#3  0x00007fa0b01d2b0f in QWaitCondition::wait(QMutex*, QDeadlineTimer) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01d2c01 in QWaitCondition::wait(QMutex*, unsigned long) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0af290109 in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fa0af2903ad in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 11 (Thread 0x7f9fe9de7700 (LWP 18769)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb721f5534) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb721f54e0, cond=0x55bb721f5508) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb721f5508, mutex=0x55bb721f54e0) at pthread_cond_wait.c:638
#3  0x00007fa0b01d2b0f in QWaitCondition::wait(QMutex*, QDeadlineTimer) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01d2c01 in QWaitCondition::wait(QMutex*, unsigned long) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0af290109 in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fa0af2903ad in ?? () from /lib/x86_64-linux-gnu/libQt5Quick.so.5
#7  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7f9feb0d0700 (LWP 18768)):
#0  0x00007fa0b1a15a66 in __ppoll (fds=0x7f9fe4000d68, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:44
#1  0x00007fa0b03e84a9 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa0b03e9a14 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01cb785 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0aef1f1a9 in ?? () from /lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7fa0a1e8b700 (LWP 18766)):
#0  0x00007fa0b1a15a66 in __ppoll (fds=0x7fa094000da8, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:44
#1  0x00007fa0b03e84a9 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa0b03e9a14 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01cb785 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0aef1f1a9 in ?? () from /lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fa0707ff700 (LWP 18765)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7fa0afdd3fb8) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7fa0afdd3f68, cond=0x7fa0afdd3f90) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x7fa0afdd3f90, mutex=0x7fa0afdd3f68) at pthread_cond_wait.c:638
#3  0x00007fa0afcd65fa in ?? () from /lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007fa0afcd661f in ?? () from /lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fa089f32700 (LWP 18759)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb71687908) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb716878b8, cond=0x55bb716878e0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb716878e0, mutex=0x55bb716878b8) at pthread_cond_wait.c:638
#3  0x00007fa08edff3db in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#4  0x00007fa08edfefeb in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#5  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7fa08a733700 (LWP 18758)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb71687908) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb716878b8, cond=0x55bb716878e0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb716878e0, mutex=0x55bb716878b8) at pthread_cond_wait.c:638
#3  0x00007fa08edff3db in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#4  0x00007fa08edfefeb in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#5  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fa0a0914700 (LWP 18757)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb71687908) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb716878b8, cond=0x55bb716878e0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb716878e0, mutex=0x55bb716878b8) at pthread_cond_wait.c:638
#3  0x00007fa08edff3db in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#4  0x00007fa08edfefeb in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#5  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fa0a1115700 (LWP 18756)):
#0  futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55bb71687908) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55bb716878b8, cond=0x55bb716878e0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x55bb716878e0, mutex=0x55bb716878b8) at pthread_cond_wait.c:638
#3  0x00007fa08edff3db in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#4  0x00007fa08edfefeb in ?? () from /usr/lib/x86_64-linux-gnu/dri/iris_dri.so
#5  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fa0a30cc700 (LWP 18754)):
#0  0x00007fa0b1a15a66 in __ppoll (fds=0x7fa090000d68, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:44
#1  0x00007fa0b03e84a9 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa0b03e9a14 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b01cb785 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fa0aef1f1a9 in ?? () from /lib/x86_64-linux-gnu/libQt5Qml.so.5
#6  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#8  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fa0a9531700 (LWP 18750)):
#0  0x00007fa0b03e9ef6 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#1  0x00007fa0b03e98c4 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007fa0b01cb785 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fa0b13fdefa in ?? () from /lib/x86_64-linux-gnu/libQt5DBus.so.5
#5  0x00007fa0b01cc9d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fa0b18e0609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fa0b1a22103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fa0aac62080 (LWP 18746)):
[KCrash Handler]
#6  0x00007fa0b165c868 in KWin::AbstractClient::setDesktops(QVector<KWin::VirtualDesktop*>) () from /lib/x86_64-linux-gnu/libkwin.so.5
#7  0x00007fa0b16c1811 in KWin::EffectsHandlerImpl::windowToDesktops(KWin::EffectWindow*, QVector<unsigned int> const&) () from /lib/x86_64-linux-gnu/libkwin.so.5
#8  0x00007fa0afe499d9 in ?? () from /lib/x86_64-linux-gnu/libkwin4_effect_builtins.so.1
#9  0x00007fa0b16c319f in KWin::EffectsHandlerImpl::checkInputWindowEvent(QMouseEvent*) () from /lib/x86_64-linux-gnu/libkwin.so.5
#10 0x00007fa0a8cf597e in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kwin.platforms/KWinX11Platform.so
#11 0x00007fa0b16cde66 in KWin::Workspace::workspaceEvent(xcb_generic_event_t*) () from /lib/x86_64-linux-gnu/libkwin.so.5
#12 0x00007fa0b0391d8f in QAbstractEventDispatcher::filterNativeEvent(QByteArray const&, void*, long*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007fa0aa5887b5 in QXcbConnection::handleXcbEvent(xcb_generic_event_t*) () from /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#14 0x00007fa0aa58978a in QXcbConnection::processXcbEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#15 0x00007fa0aa5b46f0 in ?? () from /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#16 0x00007fa0b03934db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007fa0b039b246 in QCoreApplication::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007fa0b1afb9ef in kdemain () from /lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#19 0x00007fa0b19270b3 in __libc_start_main (main=0x55bb6f1af060, argc=3, argv=0x7ffc26c00518, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffc26c00508) at ../csu/libc-start.c:308
#20 0x000055bb6f1af09e in _start ()
[Inferior 1 (process 18746) detached]