Application: systemsettings5 (5.12.0)

Qt Version: 5.10.0
Frameworks Version: 5.42.0
Operating System: Linux 4.15.0-pf2 x86_64
Distribution: "Arch Linux"

-- Information about the crash:
I changed the previous configuration which referred to specific fonts to ones that refer to generic versions(monospace, sans-serif) and clicked apply. Then the application crashed. FWIW it is the wayland session.

-- Backtrace:
Application: System Settings (systemsettings5), signal: Segmentation fault
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fd95f600800 (LWP 5530))]

Thread 5 (Thread 0x7fd923e6d700 (LWP 5544)):
#0  0x00007fd95aff63d8 in read () at /usr/lib/libc.so.6
#1  0x00007fd94b0027c2 in pa_read () at /usr/lib/pulseaudio/libpulsecommon-11.1.so
#2  0x00007fd94b4897af in pa_mainloop_prepare () at /usr/lib/libpulse.so.0
#3  0x00007fd94b48a241 in pa_mainloop_iterate () at /usr/lib/libpulse.so.0
#4  0x00007fd94b48a301 in pa_mainloop_run () at /usr/lib/libpulse.so.0
#5  0x00007fd94b4986ae in  () at /usr/lib/libpulse.so.0
#6  0x00007fd94b03281c in  () at /usr/lib/pulseaudio/libpulsecommon-11.1.so
#7  0x00007fd95717a08c in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007fd95b004e7f in clone () at /usr/lib/libc.so.6

Thread 4 (Thread 0x7fd932ca5700 (LWP 5539)):
#0  0x00007fd95affa97b in poll () at /usr/lib/libc.so.6
#1  0x00007fd954b26ff3 in  () at /usr/lib/libglib-2.0.so.0
#2  0x00007fd954b2710e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3  0x00007fd95b945d24 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007fd95b8e7e9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5  0x00007fd95b6f778e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#6  0x00007fd959222a19 in  () at /usr/lib/libQt5Qml.so.5
#7  0x00007fd95b6fcb2d in  () at /usr/lib/libQt5Core.so.5
#8  0x00007fd95717a08c in start_thread () at /usr/lib/libpthread.so.0
#9  0x00007fd95b004e7f in clone () at /usr/lib/libc.so.6

Thread 3 (Thread 0x7fd93abb0700 (LWP 5537)):
#0  0x00007fd954b6db94 in g_mutex_unlock () at /usr/lib/libglib-2.0.so.0
#1  0x00007fd954b26509 in g_main_context_prepare () at /usr/lib/libglib-2.0.so.0
#2  0x00007fd954b26f1e in  () at /usr/lib/libglib-2.0.so.0
#3  0x00007fd954b2710e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#4  0x00007fd95b945d24 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5  0x00007fd95b8e7e9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#6  0x00007fd95b6f778e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#7  0x00007fd959222a19 in  () at /usr/lib/libQt5Qml.so.5
#8  0x00007fd95b6fcb2d in  () at /usr/lib/libQt5Core.so.5
#9  0x00007fd95717a08c in start_thread () at /usr/lib/libpthread.so.0
#10 0x00007fd95b004e7f in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7fd949b42700 (LWP 5536)):
#0  0x00007fd954b6db79 in g_mutex_lock () at /usr/lib/libglib-2.0.so.0
#1  0x00007fd954b26b77 in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0
#2  0x00007fd954b27081 in  () at /usr/lib/libglib-2.0.so.0
#3  0x00007fd954b2710e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#4  0x00007fd95b945d24 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5  0x00007fd95b8e7e9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#6  0x00007fd95b6f778e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#7  0x00007fd95d26a416 in  () at /usr/lib/libQt5DBus.so.5
#8  0x00007fd95b6fcb2d in  () at /usr/lib/libQt5Core.so.5
#9  0x00007fd95717a08c in start_thread () at /usr/lib/libpthread.so.0
#10 0x00007fd95b004e7f in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7fd95f600800 (LWP 5530)):
[KCrash Handler]
#5  0x00007fd95a0091d3 in XAddExtension () at /usr/lib/libX11.so.6
#6  0x00007fd91d55da05 in  () at /usr/lib/libXft.so.2
#7  0x00007fd91d55dede in XftDefaultHasRender () at /usr/lib/libXft.so.2
#8  0x00007fd91d55e410 in XftDefaultSubstitute () at /usr/lib/libXft.so.2
#9  0x00007fd91d560d45 in XftFontMatch () at /usr/lib/libXft.so.2
#10 0x00007fd91d560ed3 in XftFontOpen () at /usr/lib/libXft.so.2
#11 0x00007fd91dc0b51a in KFI::CFcEngine::getFont(int) () at /usr/lib/libkfontinstui.so.5
#12 0x00007fd91dc0b9e4 in KFI::CFcEngine::queryFont() () at /usr/lib/libkfontinstui.so.5
#13 0x00007fd91dc0c199 in KFI::CFcEngine::getSizes() () at /usr/lib/libkfontinstui.so.5
#14 0x00007fd91dc0d889 in KFI::CFcEngine::draw(QString const&, unsigned int, int, QColor const&, QColor const&, int, int, bool, QList<KFI::CFcEngine::TRange> const&, QList<KFI::CFcEngine::TChar>*) () at /usr/lib/libkfontinstui.so.5
#15 0x00007fd91e0b245a in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#16 0x00007fd91e0e2607 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#17 0x00007fd91e0f873a in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#18 0x00007fd95b91a076 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/libQt5Core.so.5
#19 0x00007fd91e0f6bb6 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#20 0x00007fd91e0d4013 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#21 0x00007fd91e0f7eb9 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#22 0x00007fd95b91a076 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/libQt5Core.so.5
#23 0x00007fd95b893d48 in QItemSelectionModel::selectionChanged(QItemSelection const&, QItemSelection const&) () at /usr/lib/libQt5Core.so.5
#24 0x00007fd95b898761 in QItemSelectionModel::emitSelectionChanged(QItemSelection const&, QItemSelection const&) () at /usr/lib/libQt5Core.so.5
#25 0x00007fd95b89ba06 in QItemSelectionModel::select(QItemSelection const&, QFlags<QItemSelectionModel::SelectionFlag>) () at /usr/lib/libQt5Core.so.5
#26 0x00007fd95b895e0d in QItemSelectionModel::select(QModelIndex const&, QFlags<QItemSelectionModel::SelectionFlag>) () at /usr/lib/libQt5Core.so.5
#27 0x00007fd91e0cd37d in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#28 0x00007fd91e0e64be in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#29 0x00007fd91e0f884c in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#30 0x00007fd95b91a076 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/libQt5Core.so.5
#31 0x00007fd91e0f6a5f in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#32 0x00007fd91e0f7940 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#33 0x00007fd95b91a076 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/libQt5Core.so.5
#34 0x00007fd91e0f9c38 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#35 0x00007fd91e0fc0d6 in  () at /usr/lib/qt/plugins/kcm_fontinst.so
#36 0x00007fd95d275b5d in  () at /usr/lib/libQt5DBus.so.5
#37 0x00007fd95b91aac2 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5
#38 0x00007fd95c8fdecc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#39 0x00007fd95c9058a6 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#40 0x00007fd95b8e9850 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#41 0x00007fd95b8ec4b6 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/libQt5Core.so.5
#42 0x00007fd95b946714 in  () at /usr/lib/libQt5Core.so.5
#43 0x00007fd954b26e38 in g_main_context_dispatch () at /usr/lib/libglib-2.0.so.0
#44 0x00007fd954b27081 in  () at /usr/lib/libglib-2.0.so.0
#45 0x00007fd954b2710e in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#46 0x00007fd95b945d01 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#47 0x00007fd94ed8a402 in  () at /usr/lib/libQt5WaylandClient.so.5
#48 0x00007fd95b8e7e9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#49 0x00007fd95b8f1188 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#50 0x0000557124c3ad30 in  ()
#51 0x00007fd95af2ff4a in __libc_start_main () at /usr/lib/libc.so.6
#52 0x0000557124c3adba in _start ()

Reported using DrKonqi