Description of problem:

I updated to Plasma 5.18.2 in a Fedora 32 KDE Plasma spin installation with KF5 5.67, Qt 5.13.2, Mesa 20.0.0. I logged into Plasma on Wayland from sddm. 
A plasmashell segmentation fault in KScreen::GetConfigOperation::start happened at /usr/src/debug/libkscreen-qt5-5.18.2-1.fc32.x86_64/src/getconfigoperation.cpp:174. I haven't seen crashes with this trace with Plasma 5.18.1 and earlier. 

The screen went black while logging in after the splash screen. plasmashell restarted automatically. After the first such crash, the desktop icons were in four columns while they were normally in three columns. The icons were normal after the second-fourth crashes and plasmashell restarted.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
29	  return SYSCALL_CANCEL (poll, fds, nfds, timeout);
[Current thread is 1 (Thread 0x7fc64a892580 (LWP 1425))]

Thread 20 (Thread 0x7fc5f4e52700 (LWP 1867)):
#0  futex_abstimed_wait_cancelable (private=0, abstime=0x7fc5f4e51cc0, clockid=<optimized out>, expected=0, futex_word=0x5617e0e0a130) at ../sysdeps/nptl/futex-internal.h:320
#1  __pthread_cond_wait_common (abstime=0x7fc5f4e51cc0, clockid=<optimized out>, mutex=0x5617e0e0a0e0, cond=0x5617e0e0a108) at pthread_cond_wait.c:520
#2  __pthread_cond_timedwait (cond=0x5617e0e0a108, mutex=0x5617e0e0a0e0, abstime=0x7fc5f4e51cc0) at pthread_cond_wait.c:656
#3  0x00007fc648f9f4d9 in QWaitConditionPrivate::wait_relative(QDeadlineTimer) (deadline=..., this=0x5617e0e0a0e0) at thread/qwaitcondition_unix.cpp:136
#4  QWaitConditionPrivate::wait(QDeadlineTimer) (deadline=..., deadline=..., this=0x5617e0e0a0e0) at thread/qwaitcondition_unix.cpp:144
#5  QWaitCondition::wait(QMutex*, QDeadlineTimer) (this=<optimized out>, mutex=0x5617e0e09f70, deadline=...) at thread/qwaitcondition_unix.cpp:225
#6  0x00007fc648f9f5fb in QWaitCondition::wait(QMutex*, unsigned long) (this=0x5617e08884a0, mutex=0x5617e0e09f70, time=<optimized out>) at thread/qwaitcondition_unix.cpp:209
#7  0x00007fc648f9d5e3 in QThreadPoolThread::run() (this=0x5617e0888490) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:240
#8  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x5617e0888490) at thread/qthread_unix.cpp:360
#9  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 19 (Thread 0x7fc5db5e9700 (LWP 1851)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617e0a82dd8) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617e0a82d88, cond=0x5617e0a82db0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617e0a82db0, mutex=0x5617e0a82d88) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617e0a82d88, cond=0x5617e0a82db0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617e0aa1180) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 18 (Thread 0x7fc5f5a7a700 (LWP 1833)):
#0  g_source_ref (source=<optimized out>) at ../glib/gmain.c:2166
#1  0x00007fc64782b8c8 in g_source_iter_next (iter=iter@entry=0x7fc5f5a79b90, source=source@entry=0x7fc5f5a79b88) at ../glib/gmain.c:1046
#2  0x00007fc64782ce8b in g_main_context_prepare (context=context@entry=0x7fc5d4000c30, priority=priority@entry=0x7fc5f5a79c10) at ../glib/gmain.c:3597
#3  0x00007fc64782d96b in g_main_context_iterate (context=context@entry=0x7fc5d4000c30, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4027
#4  0x00007fc64782db73 in g_main_context_iteration (context=0x7fc5d4000c30, may_block=may_block@entry=1) at ../glib/gmain.c:4108
#5  0x00007fc64916fb93 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fc5d4000b60, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#6  0x00007fc6491231db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fc5f5a79d60, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#7  0x00007fc648f986e7 in QThread::exec() (this=<optimized out>) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#8  0x00007fc5f62ef62c in KCupsConnection::run() () at /lib64/libkcupslib.so
#9  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x5617e07c5b00) at thread/qthread_unix.cpp:360
#10 0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#11 0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 17 (Thread 0x7fc5fd21e700 (LWP 1820)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617e0054504) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617e00544b0, cond=0x5617e00544d8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617e00544d8, mutex=0x5617e00544b0) at pthread_cond_wait.c:638
#3  0x00007fc648f9f5a3 in QWaitConditionPrivate::wait(QDeadlineTimer) (deadline=..., deadline=..., this=0x5617e00544b0) at thread/qwaitcondition_unix.cpp:146
#4  QWaitCondition::wait(QMutex*, QDeadlineTimer) (this=<optimized out>, mutex=0x5617dffb74d0, deadline=...) at thread/qwaitcondition_unix.cpp:225
#5  0x00007fc64aa5af64 in QSGRenderThreadEventQueue::takeEvent(bool) (wait=true, this=0x5617dffb74c8) at scenegraph/qsgthreadedrenderloop.cpp:245
#6  QSGRenderThread::processEventsAndWaitForMore() (this=this@entry=0x5617dffb7450) at scenegraph/qsgthreadedrenderloop.cpp:710
#7  0x00007fc64aa5c44d in QSGRenderThread::run() (this=0x5617dffb7450) at scenegraph/qsgthreadedrenderloop.cpp:739
#8  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x5617dffb7450) at thread/qthread_unix.cpp:360
#9  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 16 (Thread 0x7fc5fda1f700 (LWP 1818)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617e012f078) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617e012f028, cond=0x5617e012f050) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617e012f050, mutex=0x5617e012f028) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617e012f028, cond=0x5617e012f050) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617e014d450) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 15 (Thread 0x7fc5fe226700 (LWP 1817)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617e0098ae8) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617e0098a98, cond=0x5617e0098ac0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617e0098ac0, mutex=0x5617e0098a98) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617e0098a98, cond=0x5617e0098ac0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617e0053d60) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 14 (Thread 0x7fc5ff432700 (LWP 1815)):
#0  0x00007fc64787c08d in g_mutex_lock (mutex=mutex@entry=0x7fc5e8000c30) at ../glib/gthread-posix.c:1481
#1  0x00007fc64782cba8 in g_main_context_release (context=0x7fc5e8000c30) at ../glib/gmain.c:3409
#2  0x00007fc64782d9fa in g_main_context_iterate (context=context@entry=0x7fc5e8000c30, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4049
#3  0x00007fc64782db73 in g_main_context_iteration (context=0x7fc5e8000c30, may_block=may_block@entry=1) at ../glib/gmain.c:4108
#4  0x00007fc64916fb93 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fc5e8000b60, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007fc6491231db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fc5ff431d60, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#6  0x00007fc648f986e7 in QThread::exec() (this=this@entry=0x5617df991180) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#7  0x00007fc64a9db11a in QQuickPixmapReader::run() (this=0x5617df991180) at util/qquickpixmapcache.cpp:962
#8  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x5617df991180) at thread/qthread_unix.cpp:360
#9  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 13 (Thread 0x7fc621f87700 (LWP 1808)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc70618) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc705c8, cond=0x5617dfc705f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc705f0, mutex=0x5617dfc705c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc705c8, cond=0x5617dfc705f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc718b0) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7fc622788700 (LWP 1807)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc70618) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc705c8, cond=0x5617dfc705f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc705f0, mutex=0x5617dfc705c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc705c8, cond=0x5617dfc705f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc71870) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 11 (Thread 0x7fc622f89700 (LWP 1806)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc6ff10) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc6fec0, cond=0x5617dfc6fee8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc6fee8, mutex=0x5617dfc6fec0) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc6fec0, cond=0x5617dfc6fee8) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc6f160) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7fc62378a700 (LWP 1805)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc6ff10) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc6fec0, cond=0x5617dfc6fee8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc6fee8, mutex=0x5617dfc6fec0) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc6fec0, cond=0x5617dfc6fee8) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc6ef40) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7fc62cab6700 (LWP 1804)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc6ff14) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc6fec0, cond=0x5617dfc6fee8) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc6fee8, mutex=0x5617dfc6fec0) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc6fec0, cond=0x5617dfc6fee8) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc71810) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fc62d2b7700 (LWP 1803)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfbba918) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfbba8c8, cond=0x5617dfbba8f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfbba8f0, mutex=0x5617dfbba8c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfbba8c8, cond=0x5617dfbba8f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc717b0) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fc62dab8700 (LWP 1802)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfbba918) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfbba8c8, cond=0x5617dfbba8f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfbba8f0, mutex=0x5617dfbba8c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfbba8c8, cond=0x5617dfbba8f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc71770) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7fc62e2b9700 (LWP 1801)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfbba918) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfbba8c8, cond=0x5617dfbba8f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfbba8f0, mutex=0x5617dfbba8c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfbba8c8, cond=0x5617dfbba8f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc71730) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fc62eaba700 (LWP 1800)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfbba918) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfbba8c8, cond=0x5617dfbba8f0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfbba8f0, mutex=0x5617dfbba8c8) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfbba8c8, cond=0x5617dfbba8f0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc70fd0) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fc63527a700 (LWP 1799)):
#0  futex_wait_cancelable (private=0, expected=0, futex_word=0x5617dfc6bdcc) at ../sysdeps/nptl/futex-internal.h:183
#1  __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x5617dfc6bd78, cond=0x5617dfc6bda0) at pthread_cond_wait.c:508
#2  __pthread_cond_wait (cond=0x5617dfc6bda0, mutex=0x5617dfc6bd78) at pthread_cond_wait.c:638
#3  0x00007fc62f30a07b in cnd_wait (mtx=0x5617dfc6bd78, cond=0x5617dfc6bda0) at ../include/c11/threads_posix.h:155
#4  util_queue_thread_func (input=input@entry=0x5617dfc68a80) at ../src/util/u_queue.c:275
#5  0x00007fc62f309b5b in impl_thrd_routine (p=<optimized out>) at ../include/c11/threads_posix.h:87
#6  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#7  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fc63694a700 (LWP 1773)):
#0  0x00007fc64782d282 in g_main_context_check (context=context@entry=0x7fc628000c30, max_priority=2147483647, fds=fds@entry=0x7fc6280029e0, n_fds=n_fds@entry=1) at ../glib/gmain.c:3799
#1  0x00007fc64782d9e3 in g_main_context_iterate (context=context@entry=0x7fc628000c30, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4044
#2  0x00007fc64782db73 in g_main_context_iteration (context=0x7fc628000c30, may_block=may_block@entry=1) at ../glib/gmain.c:4108
#3  0x00007fc64916fb93 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fc628000b60, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#4  0x00007fc6491231db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fc636949d80, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#5  0x00007fc648f986e7 in QThread::exec() (this=this@entry=0x5617df9dbcc0) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#6  0x00007fc64a6f0d89 in QQmlThreadPrivate::run() (this=0x5617df9dbcc0) at qml/ftw/qqmlthread.cpp:152
#7  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x5617df9dbcc0) at thread/qthread_unix.cpp:360
#8  0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#9  0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fc637be2700 (LWP 1456)):
#0  0x00007fc647829b9d in g_source_unref_internal (source=0x7fc630005070, context=0x7fc630000c30, have_lock=1) at ../glib/gmain.c:2184
#1  0x00007fc64782b8e5 in g_source_iter_next (iter=iter@entry=0x7fc637be1b80, source=source@entry=0x7fc637be1b78) at ../glib/gmain.c:1049
#2  0x00007fc64782ce8b in g_main_context_prepare (context=context@entry=0x7fc630000c30, priority=priority@entry=0x7fc637be1c00) at ../glib/gmain.c:3597
#3  0x00007fc64782d96b in g_main_context_iterate (context=context@entry=0x7fc630000c30, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4027
#4  0x00007fc64782db73 in g_main_context_iteration (context=0x7fc630000c30, may_block=may_block@entry=1) at ../glib/gmain.c:4108
#5  0x00007fc64916fb93 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fc630000b60, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#6  0x00007fc6491231db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fc637be1d50, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#7  0x00007fc648f986e7 in QThread::exec() (this=<optimized out>) at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#8  0x00007fc64a0744da in QDBusConnectionManager::run() (this=0x7fc64a0e2060 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#9  0x00007fc648f999b6 in QThreadPrivate::start(void*) (arg=0x7fc64a0e2060 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:360
#10 0x00007fc6484b4432 in start_thread (arg=<optimized out>) at pthread_create.c:477
#11 0x00007fc648c1c833 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fc64a892580 (LWP 1425)):
[KCrash Handler]
#6  KScreen::GetConfigOperation::start() (this=0x5617dfe74700) at /usr/src/debug/libkscreen-qt5-5.18.2-1.fc32.x86_64/src/getconfigoperation.cpp:174
#7  0x00007fc64914b312 in QObject::event(QEvent*) (this=0x5617dfe74700, e=<optimized out>) at kernel/qobject.cpp:1260
#8  0x00007fc649a8ae66 in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0x5617dfe74700, e=0x5617e07ac470) at kernel/qapplication.cpp:3703
#9  0x00007fc649124860 in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0x5617dfe74700, event=0x5617e07ac470) at ../../include/QtCore/../../src/corelib/kernel/qobject.h:143
#10 0x00007fc649127af3 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (receiver=0x0, event_type=0, data=0x5617df8c6770) at kernel/qcoreapplication.cpp:1840
#11 0x00007fc6491700f7 in postEventSourceDispatch(GSource*, GSourceFunc, gpointer) (s=s@entry=0x5617df8feff0) at kernel/qeventdispatcher_glib.cpp:277
#12 0x00007fc64782d71f in g_main_dispatch (context=0x5617df8ede40) at ../glib/gmain.c:3309
#13 g_main_context_dispatch (context=0x5617df8ede40) at ../glib/gmain.c:3974
#14 0x00007fc64782daa8 in g_main_context_iterate (context=context@entry=0x5617df8ede40, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4047
#15 0x00007fc64782db73 in g_main_context_iteration (context=0x5617df8ede40, may_block=may_block@entry=1) at ../glib/gmain.c:4108
#16 0x00007fc64916fb75 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x5617df9003d0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#17 0x00007fc6491231db in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7ffd9aef0ff0, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#18 0x00007fc64912adb6 in QCoreApplication::exec() () at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#19 0x00005617df616b7f in main ()
[Inferior 1 (process 1425) detached]

Version-Release number of selected component (if applicable):
plasma-workspace-5.18.2-1.fc32.x86_64
kf5-kwayland-5.67.0-1.fc32.x86_64
mesa-dri-drivers-20.0.0-1.fc32.x86_64
qt5-qtbase-5.13.2-3.fc32.x86_64
sddm-0.18.1-4.fc32.x86_64

How reproducible:
This crash happened 4/4 times when logging into Plasma 5.18.2.


Steps to Reproduce:
1. Boot F32 KDE Plasma spin installation with kwin-wayland, plasma-workspace-wayland and their dependencies installed
2. Update to Plasma 5.18.2 https://bodhi.fedoraproject.org/updates/FEDORA-2020-adc0006108
3. Reboot
4. Log in to Plasma 5.18.2 from sddm

Actual results:
plasmashell segmentation fault in KScreen::GetConfigOperation::start when logging into Plasma 5.18.2 on Wayland

Expected results:
plasmashell wouldn't crash.

Additional info:

These plasmashell crashes might be related to the patch for the kded5 crashes when logging into Plasma 5.17.90 and later on Wayland at https://bugs.kde.org/show_bug.cgi?id=416566#c6 https://bugzilla.redhat.com/show_bug.cgi?id=1793886
The kded5 crashing thread had functions with Config in their names in libkscreen-qt5 in frame #8 KScreen::WaylandConfig::applyConfig at /usr/src/debug/libkscreen-qt5-5.18.0-1.fc32.x86_64/backends/kwayland/waylandconfig.cpp:330 and #9 KScreen::SetConfigOperation::start() at /usr/src/debug/libkscreen-qt5-5.18.0-1.fc32.x86_64/src/setconfigoperation.cpp:129
https://bugs.kde.org/show_bug.cgi?id=416566#c2