SUMMARY
DiscoverNotifier crashed after I add flathub and after I add and remove
https://firefox-flatpak.mojefedora.cz/org.mozilla.FirefoxRepo.flatpakrepo
via "Settings" page.

Operating System: KDE neon Unstable Edition
KDE Plasma Version: 5.18.80
KDE Frameworks Version: 5.67.0
Qt Version: 5.13.2


Thread 5 (Thread 0x7fcfa5aab700 (LWP 14247)):
#0  0x00007fcfbc2afbf9 in __GI___poll (fds=0x7fcfa001c2b0, nfds=5, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fcfb75c85c9 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fcfb75c86dc in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fcfbcc02b7f in QEventDispatcherGlib::unregisterTimers (this=<optimized out>, object=0x5)
    at kernel/qeventdispatcher_glib.cpp:556
#4  0x00007fcfa0004770 in ?? ()
#5  0x00007fcfa0004770 in ?? ()
#6  0x0000000000000024 in ?? ()
#7  0x00007fcfa5aaad70 in ?? ()
#8  0x00007fcfa00047e4 in ?? ()
#9  0x00005589f1ae0590 in ?? ()
#10 0x00007ffc648de5d0 in ?? ()
#11 0x00007fcfbcba306a in QVector<QEventLoop*>::detach (this=0x4)
    at ../../include/QtCore/../../src/corelib/tools/qvector.h:396
#12 QVector<QEventLoop*>::begin (this=0x4) at ../../include/QtCore/../../src/corelib/tools/qvector.h:210
#13 QVector<QEventLoop*>::resize (asize=0, this=0x4) at ../../include/QtCore/../../src/corelib/tools/qvector.h:425
#14 QStack<QEventLoop*>::pop (this=0x4) at ../../include/QtCore/../../src/corelib/tools/qstack.h:63
#15 QEventLoop::LoopReference::~LoopReference (this=<synthetic pointer>, __in_chrg=<optimized out>)
    at kernel/qeventloop.cpp:201
#16 QEventLoop::exec (this=this@entry=0x7fcfa5aaad70, flags=..., flags@entry=...) at kernel/qeventloop.cpp:208
#17 0x00007fcfbc9be3aa in QThread::exec (
    this=this@entry=0x7fcfbd590d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>)
    at thread/qthread.cpp:531
#18 0x00007fcfbd3190e5 in QDBusConnectionManager::run (
    this=0x7fcfbd590d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#19 0x00007fcfbc9bfb52 in QThreadPrivate::start (
    arg=0x7fcfbd590d80 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:360
#20 0x00007fcfb97656db in start_thread (arg=0x7fcfa5aab700) at pthread_create.c:463
#21 0x00007fcfbc2bc88f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fcf96466700 (LWP 14328)):
#0  0x00007fcfbc2afbf9 in __GI___poll (fds=0x5589f1ba20c0, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fcfb75c85c9 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fcfb75c86dc in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fcfb75c8721 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fcfb75f0195 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fcfb97656db in start_thread (arg=0x7fcf96466700) at pthread_create.c:463
#6  0x00007fcfbc2bc88f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fcf97512700 (LWP 14327)):
#0  0x00007fcfbc2afbf9 in __GI___poll (fds=0x7fcf90004a10, nfds=1, timeout=9990) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fcfb75c85c9 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fcfb75c86dc in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fcfbcc02b7f in QEventDispatcherGlib::unregisterTimers (this=<optimized out>, object=0x1)
    at kernel/qeventdispatcher_glib.cpp:556
#4  0x00007fcf90004370 in ?? ()
#5  0x00007fcf90004370 in ?? ()
#6  0x0000000000000024 in ?? ()
#7  0x00007fcf97511da0 in ?? ()
#8  0x00007fcf900043e4 in ?? ()
#9  0x00005589f1b74480 in ?? ()
#10 0x00007ffc648de5d0 in ?? ()
#11 0x00007fcfbcba306a in QVector<QEventLoop*>::detach (this=0x4)
    at ../../include/QtCore/../../src/corelib/tools/qvector.h:396
#12 QVector<QEventLoop*>::begin (this=0x4) at ../../include/QtCore/../../src/corelib/tools/qvector.h:210
#13 QVector<QEventLoop*>::resize (asize=0, this=0x4) at ../../include/QtCore/../../src/corelib/tools/qvector.h:425
#14 QStack<QEventLoop*>::pop (this=0x4) at ../../include/QtCore/../../src/corelib/tools/qstack.h:63
#15 QEventLoop::LoopReference::~LoopReference (this=<synthetic pointer>, __in_chrg=<optimized out>)
    at kernel/qeventloop.cpp:201
#16 QEventLoop::exec (this=this@entry=0x7fcf97511da0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:208
#17 0x00007fcfbc9be3aa in QThread::exec (this=<optimized out>) at thread/qthread.cpp:531
#18 0x00007fcfbc9bfb52 in QThreadPrivate::start (arg=0x5589f1adc500) at thread/qthread_unix.cpp:360
#19 0x00007fcfb97656db in start_thread (arg=0x7fcf97512700) at pthread_create.c:463
#20 0x00007fcfbc2bc88f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fcfae19c700 (LWP 14246)):
#0  0x00007fcfbc2afbf9 in __GI___poll (fds=0x7fcfae19bca8, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fcfb735f747 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007fcfb736136a in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007fcfb0f81e10 in QXcbEventQueue::run (this=0x5589f1a76000) at qxcbeventqueue.cpp:228
#4  0x00007fcfbc9bfb52 in QThreadPrivate::start (arg=0x5589f1a76000) at thread/qthread_unix.cpp:360
#5  0x00007fcfb97656db in start_thread (arg=0x7fcfae19c700) at pthread_create.c:463
#6  0x00007fcfbc2bc88f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fcfbfbf0800 (LWP 14243)):
#0  __GI_raise (sig=sig@entry=7) at ../sysdeps/unix/sysv/linux/raise.c:51
#1  0x00007fcfbf05ad33 in KCrash::defaultCrashHandler (sig=7) at ./src/kcrash.cpp:472
#2  <signal handler called>
#3  QMetaCallEvent::~QMetaCallEvent (this=0x6b617074616c662f, __in_chrg=<optimized out>) at kernel/qobject.cpp:497
#4  0x00007fcfbcc8cf80 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x0000000000000000 in ?? ()