SUMMARY
kde platform runtime was the only update available, DiscoverNotifier crashed
while Discover installed it. Discover shown the error "Aborted due failure"
but apparently the update was installed because it disappeared from "Update"
page. I ran "flatpak update" and 2 updates was found:
org.freedesktop.Platform.openh264/x86_64/19.08 flathub c0f2ca316dfb
org.kde.Platform.Locale/x86_64/5.14 flathub 07ec4c1b4d3f


SOFTWARE/OS VERSIONS
Operating System: KDE neon Unstable Edition
KDE Plasma Version: 5.18.80
KDE Frameworks Version: 5.68.0
Qt Version: 5.14.1


Thread 6 (Thread 0x7f472a9c3700 (LWP 9318)):
#0  0x00007f4750a84bf9 in __GI___poll (fds=0x56427702cde0, nfds=2, timeout=-1)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f474bda05c9 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f474bda06dc in g_main_context_iteration ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f474bda0721 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f474bdc8195 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f474df3d6db in start_thread (arg=0x7f472a9c3700) at pthread_create.c:463
#6  0x00007f4750a9188f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f473a0fa700 (LWP 9281)):
#0  0x00007f4750a84bf9 in __GI___poll (fds=0x7f473401c660, nfds=5, timeout=-1)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f474bda05c9 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f474bda06dc in g_main_context_iteration ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f47513eb0bc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f4734000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#4  0x00007f475138a63a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f473a0f9d70, flags=..., flags@entry=...) at kernel/qeventloop.cpp:225
#5  0x00007f475119b317 in QThread::exec() (this=this@entry=0x7f4751d90da0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread.cpp:536
#6  0x00007f4751b18555 in QDBusConnectionManager::run() (this=0x7f4751d90da0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:179
#7  0x00007f475119c7ec in QThreadPrivate::start(void*) (arg=0x7f4751d90da0 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:342
#8  0x00007f474df3d6db in start_thread (arg=0x7f473a0fa700) at pthread_create.c:463
#9  0x00007f4750a9188f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f4742ba3700 (LWP 9280)):
#0  0x00007f4750a84bf9 in __GI___poll (fds=0x7f4742ba2ca8, nfds=1, timeout=-1)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f474bb37747 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f474bb3936a in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f4745778cc0 in QXcbEventQueue::run() (this=0x564276f2a770)
    at qxcbeventqueue.cpp:228
#4  0x00007f475119c7ec in QThreadPrivate::start(void*) (arg=0x564276f2a770)
    at thread/qthread_unix.cpp:342
#5  0x00007f474df3d6db in start_thread (arg=0x7f4742ba3700) at pthread_create.c:463
#6  0x00007f4750a9188f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f472a1c2700 (LWP 9319)):
#0  0x00007f4750a84bf9 in __GI___poll (fds=0x564277056240, nfds=2, timeout=-1)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f474bda05c9 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f474bda0962 in g_main_loop_run () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4738d270e6 in  () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#4  0x00007f474bdc8195 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f474df3d6db in start_thread (arg=0x7f472a1c2700) at pthread_create.c:463
#6  0x00007f4750a9188f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f472bcbf700 (LWP 9317)):
#0  0x00007f4750a84bf9 in __GI___poll (fds=0x7f47240029e0, nfds=1, timeout=9985)
    at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f474bda05c9 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f474bda06dc in g_main_context_iteration ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f47513eb0bc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7f4724000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#4  0x00007f475138a63a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7f472bcbeda0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:225
#5  0x00007f475119b317 in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:536
#6  0x00007f475119c7ec in QThreadPrivate::start(void*) (arg=0x564276fd9210)
    at thread/qthread_unix.cpp:342
#7  0x00007f474df3d6db in start_thread (arg=0x7f472bcbf700) at pthread_create.c:463
#8  0x00007f4750a9188f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f47544b6800 (LWP 9278)):
#0  0x00007f47509aee97 in __GI_raise (sig=sig@entry=7)
    at ../sysdeps/unix/sysv/linux/raise.c:51
#1  0x00007f4753932d33 in KCrash::defaultCrashHandler(int) (sig=7) at ./src/kcrash.cpp:472
#2  0x00007f47509aef20 in <signal handler called> () at /lib/x86_64-linux-gnu/libc.so.6
#3  0x00007f47513ba0f9 in check_parent_thread(QObject*, QThreadData*, QThreadData*) (parent=parent@entry=0x564276f93d78, parentThreadData=<optimized out>, currentThreadData=<optimized out>) at kernel/qobject.cpp:884
#4  0x00007f47513c5408 in check_parent_thread (currentThreadData=<optimized out>, parentThreadData=<optimized out>, parent=0x564276f93d78) at kernel/qobject.cpp:945
#5  0x00007f47513c5408 in QObject::QObject(QObjectPrivate&, QObject*) (this=0x7f473c005f80, dd=..., parent=0x564276f93d78) at kernel/qobject.cpp:949
#6  0x00007f47511a6bfb in QFutureWatcherBase::QFutureWatcherBase(QObject*) (this=0x7f473c005f80, parent=0x564276f93d78) at thread/qfuturewatcher.cpp:106
#7  0x00007f473929d093 in QFutureWatcher<_GPtrArray*>::QFutureWatcher(QObject*) (_parent=0x564276f93d78, this=0x7f473c005f80)
    at /usr/include/x86_64-linux-gnu/qt5/QtCore/qfuturewatcher.h:118
#8  0x00007f473929d093 in FlatpakNotifier::loadRemoteUpdates(FlatpakNotifier::Installation*) (this=0x564276f93d78, installation=0x564276f93da0)
    at ./libdiscover/backends/FlatpakBackend/FlatpakNotifier.cpp:112
#9  0x00007f473a99edae in ffi_call_unix64 () at /usr/lib/x86_64-linux-gnu/libffi.so.6
#10 0x00007f473a99e71f in ffi_call () at /usr/lib/x86_64-linux-gnu/libffi.so.6
#11 0x00007f4738a14ced in g_cclosure_marshal_generic_va ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#12 0x00007f4738a14346 in  () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#13 0x00007f4738a2f9ff in g_signal_emit_valist ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#14 0x00007f4738a3012f in g_signal_emit ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#15 0x00007f4738d41059 in  () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#16 0x00007f474bda0417 in g_main_context_dispatch ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#17 0x00007f474bda0650 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007f474bda06dc in g_main_context_iteration ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f47513eb0bc in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x564276f7d5f0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#20 0x00007f475138a63a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7ffc1aadd8f0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:225
#21 0x00007f4751393db0 in QCoreApplication::exec() () at kernel/qcoreapplication.cpp:1400
#22 0x000056427690c7ac in main(int, char**) (argc=1, argv=0x7ffc1aaddb68)
    at /home/stalker/discover/notifier/main.cpp:91