SUMMARY
I tried setting a new global shortcut but then decided to close the window in systemsettings and when i pressed decline  
it crashed. It is reproducible each time.

Backtrace: 
#0  __pthread_kill_implementation (threadid=<optimized out>, 
    signo=signo@entry=11, no_tid=no_tid@entry=0) at pthread_kill.c:44
#1  0x00007f6d6888e3d3 in __pthread_kill_internal (signo=11, 
    threadid=<optimized out>) at pthread_kill.c:78
#2  0x00007f6d6883e838 in __GI_raise (sig=11) at ../sysdeps/posix/raise.c:26
#3  0x00007f6d6a7d7840 in KCrash::defaultCrashHandler (sig=11)
    at /usr/src/debug/kcrash-5.94.0/src/kcrash.cpp:633
#4  <signal handler called>
#5  _q_uuidToHex (uuid=..., dst=0x7fff95b45681 "X\264\225\377\177", 
    dst@entry=0x7fff95b45680 "{X\264\225\377\177", 
    mode=mode@entry=QUuid::WithBraces) at plugin/quuid.cpp:90
#6  0x00007f6d6927d2fd in QUuid::toString (this=this@entry=0x20)
    at plugin/quuid.cpp:608
#7  0x00007f6d3658c4c8 in KHotKeys::ShortcutTrigger::shortcut (this=0x0)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/triggers/shortcut_trigger.cpp:166
#8  0x00007f6d3658c82a in KHotKeys::ShortcutTrigger::primaryShortcut (
    this=<optimized out>)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/triggers/shortcut_trigger.cpp:177
#9  0x00007f6d365f9a8d in ShortcutTriggerWidget::isChanged (this=0x7fff95b45768)
    at /usr/src/debug/khotkeys-5.24.5/kcm_hotkeys/triggers/shortcut_trigger_widget.cpp:65
#10 0x00007f6d366020bb in HotkeysWidgetIFace::slotChanged (this=0x56236534f0e0)
--Type <RET> for more, q to quit, c to continue without paging--
   t /usr/src/debug/khotkeys-5.24.5/kcm_hotkeys/hotkeys_widget_iface.cpp:41
#11 0x00007f6d692be7c8 in doActivate<false> (sender=0x562365d46170, 
    signal_index=4, argv=0x7fff95b458b0) at kernel/qobject.cpp:3898
#12 0x00007f6d692bef7a in QSignalMapper::mapped (
    this=this@entry=0x562365d46170, _t1=...) at .moc/moc_qsignalmapper.cpp:231
#13 0x00007f6d692bf160 in QSignalMapperPrivate::emitMappedValue<void (QSignalMapper::*)(QString const&), QHash<QObject*, QString> > (this=0x562365cb34a0, 
    mappedValues=..., 
    signal=(void (QSignalMapper::*)(QSignalMapper * const, const QString &)) 0x7f6d692beda0 <QSignalMapper::mappedString(QString const&)>, sender=0x5623652c96f0)
    at kernel/qsignalmapper.cpp:67
#14 QSignalMapperPrivate::emitMappedValues (sender=0x5623652c96f0, 
    this=0x562365cb34a0) at kernel/qsignalmapper.cpp:77
#15 QSignalMapper::map (this=<optimized out>, sender=0x5623652c96f0)
    at kernel/qsignalmapper.cpp:288
#16 0x00007f6d692be7c8 in doActivate<false> (sender=0x5623652c96f0, 
    signal_index=7, argv=0x7fff95b459d0) at kernel/qobject.cpp:3898
#17 0x00007f6d6a8cbd47 in KKeySequenceWidget::keySequenceChanged (
    this=<optimized out>, _t1=...)
    at /usr/src/debug/build/src/KF5XmlGui_autogen/include/moc_kkeysequencewidget.cpp:253
#18 0x00007f6d692be791 in QtPrivate::QSlotObjectBase::call (a=<optimized out>, 
--Type <RET> for more, q to quit, c to continue without paging--
    r=<optimized out>, this=<optimized out>, this=<optimized out>, 
    r=<optimized out>, a=<optimized out>)
    at ../../include/QtCore/../../src/corelib/kernel/qobjectdefs_impl.h:398
#19 doActivate<false> (
    sender=0x7f6d695880b0 <(anonymous namespace)::Q_QGS_s_instance::innerFunction()::holder>, signal_index=3, argv=0x7fff95b45ad0) at kernel/qobject.cpp:3886
#20 0x00007f6d69572d89 in KGlobalAccel::globalShortcutChanged (
    this=<optimized out>, _t1=<optimized out>, _t1@entry=0x5623667d7820, 
    _t2=...)
    at /usr/src/debug/build/src/KF5GlobalAccel_autogen/include/moc_kglobalaccel.cpp:148
#21 0x00007f6d6957bae4 in KGlobalAccelPrivate::updateGlobalShortcut (
    this=<optimized out>, action=<optimized out>, action@entry=0x5623667d7820, 
    actionFlags=actionFlags@entry=..., 
    globalFlags=globalFlags@entry=KGlobalAccel::Autoloading)
    at /usr/src/debug/kglobalaccel-5.94.0/src/kglobalaccel.cpp:364
#22 0x00007f6d6957be01 in KGlobalAccel::setShortcut (
    this=this@entry=0x7f6d695880b0 <(anonymous namespace)::Q_QGS_s_instance::innerFunction()::holder>, action=<optimized out>, action@entry=0x5623667d7820, 
    shortcut=..., loadFlag=loadFlag@entry=KGlobalAccel::Autoloading)
    at /usr/include/qt/QtCore/qflags.h:121
#23 0x00007f6d3658f5de in KHotKeys::ShortcutsHandler::addAction (shortcut=..., 
--Type <RET> for more, q to quit, c to continue without paging--
    text=..., id=..., this=0x5623668ef8e0)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/shortcuts_handler.cpp:69
#24 KHotKeys::ShortcutTrigger::activate (this=0x5623668bb5b0, 
    newState=<optimized out>)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/triggers/shortcut_trigger.cpp:70
#25 0x00007f6d36589ba0 in non-virtual thunk to KHotKeys::ShortcutTrigger::enable() ()
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/triggers/shortcut_trigger.cpp:149
#26 0x00007f6d3658203c in KHotKeys::SimpleActionData::doEnable (
    this=0x5623668bb410)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/action_data/simple_action_data.cpp:36
#27 0x00007f6d36598bf1 in SettingsReaderV2::readActionData (
    this=this@entry=0x7fff95b45fe0, config=..., 
    parent=parent@entry=0x562364cb7d90)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings_reader_v2.cpp:169
#28 0x00007f6d365979db in SettingsReaderV2::readGroup (parent=<optimized out>, 
    config=..., this=0x7fff95b45fe0)
--Type <RET> for more, q to quit, c to continue without paging--
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings_reader_v2.cpp:98
#29 SettingsReaderV2::readActionData (this=0x7fff95b45fe0, config=..., 
    parent=<optimized out>)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings_reader_v2.cpp:130
#30 0x00007f6d365914b2 in SettingsReaderV2::read (parent=0x5623660d06a0, 
    config=..., this=0x7fff95b45fe0)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings_reader_v2.cpp:49
#31 KHotKeys::Settings::read_settings (stateStrategy=<optimized out>, 
    include_disabled=168, config=..., root=0x5623660d06a0, this=0x7fff95b45fa0)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings.cpp:405
#32 KHotKeys::Settings::read_settings (this=this@entry=0x7f6d540087d0, 
    root=0x5623660d06a0, config=..., 
    include_disabled=include_disabled@entry=true, 
    stateStrategy=stateStrategy@entry=KHotKeys::Retain)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings.cpp:392
#33 0x00007f6d36593317 in KHotKeys::Settings::reread_settings (
    this=this@entry=0x7f6d540087d0, 
    include_disabled=include_disabled@entry=true)
    at /usr/src/debug/khotkeys-5.24.5/libkhotkeysprivate/settings.cpp:386
--Type <RET> for more, q to quit, c to continue without paging--c
#34 0x00007f6d365eba5d in KHotkeysModel::load (this=0x7f6d540087c0) at /usr/src/debug/khotkeys-5.24.5/kcm_hotkeys/hotkeys_model.cpp:383
#35 KCMHotkeysPrivate::load (this=0x56236552f7b0) at /usr/src/debug/khotkeys-5.24.5/kcm_hotkeys/kcm_hotkeys.cpp:238
#36 KCMHotkeys::load (this=<optimized out>) at /usr/src/debug/khotkeys-5.24.5/kcm_hotkeys/kcm_hotkeys.cpp:175
#37 0x00007f6d69ccb086 in KCModuleProxy::load (this=this@entry=0x562364cb9810) at /usr/src/debug/kcmutils-5.94.0/src/kcmoduleproxy.cpp:272
#38 0x00007f6d6a954fe9 in ModuleView::resolveChanges (currentProxy=0x562364cb9810, this=0x562364c9fbd0) at /usr/src/debug/systemsettings-5.24.5/core/ModuleView.cpp:328
#39 ModuleView::resolveChanges (this=0x562364c9fbd0, currentProxy=0x562364cb9810) at /usr/src/debug/systemsettings-5.24.5/core/ModuleView.cpp:309
#40 0x00007f6d6a9550df in ModuleView::resolveChanges (this=<optimized out>) at /usr/src/debug/systemsettings-5.24.5/core/ModuleView.cpp:306
#41 0x00007f6d603178cd in SidebarMode::loadModule (this=0x562364fe85e0, activeModule=..., args=...) at /usr/src/debug/systemsettings-5.24.5/sidebar/SidebarMode.cpp:476
#42 0x00007f6d6031b0a4 in SidebarMode::loadModule (args=..., activeModule=..., this=0x562364fe85e0) at /usr/include/qt/QtCore/qabstractitemmodel.h:76
#43 SidebarMode::qt_static_metacall (_o=0x562364fe85e0, _c=<optimized out>, _id=<optimized out>, _a=0x7fff95b46620) at /usr/src/debug/build/sidebar/systemsettings_sidebar_mode_autogen/EWIEGA46WW/moc_SidebarMode.cpp:525
#44 0x00007f6d6031bc93 in SidebarMode::qt_metacall (this=0x562364fe85e0, _c=QMetaObject::InvokeMetaMethod, _id=20, _a=0x7fff95b46620) at /usr/src/debug/build/sidebar/systemsettings_sidebar_mode_autogen/EWIEGA46WW/moc_SidebarMode.cpp:661
#45 0x00007f6d67c76634 in QQmlObjectOrGadget::metacall (this=0x7fff95b468c0, type=QMetaObject::InvokeMetaMethod, index=<optimized out>, argv=<optimized out>) at /usr/src/debug/qtdeclarative/src/qml/qml/qqmlobjectorgadget.cpp:51
#46 0x00007f6d67b7a89c in CallMethod (callType=<optimized out>, callArgs=0x7fff95b46570, engine=<optimized out>, argTypes=<optimized out>, argCount=<optimized out>, returnType=<optimized out>, index=<optimized out>, object=...) at /usr/include/qt/QtCore/qvarlengtharray.h:189
#47 CallPrecise (object=..., data=..., engine=engine@entry=0x562364d12e10, callArgs=callArgs@entry=0x7f6d4c9c05b0, callType=callType@entry=QMetaObject::InvokeMetaMethod) at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4qobjectwrapper.cpp:1568
#48 0x00007f6d67b7be9d in CallOverloaded (callType=QMetaObject::InvokeMetaMethod, propertyCache=0x562365261c20, callArgs=0x7f6d4c9c05b0, engine=0x562364d12e10, data=..., object=...) at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4qobjectwrapper.cpp:1644
#49 QV4::QObjectMethod::callInternal (this=<optimized out>, thisObject=<optimized out>, argv=<optimized out>, argc=<optimized out>) at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4qobjectwrapper.cpp:2132
#50 0x00007f6d67b8df63 in QV4::Moth::VME::interpret (frame=0x7fff95b46cd0, engine=0x562364d12e10, code=0x7f6d4c9c0538 "\200dbLm\177") at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4vme_moth.cpp:757
#51 0x00007f6d67b97d64 in QV4::Moth::VME::exec (frame=<optimized out>, engine=<optimized out>) at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4vme_moth.cpp:466
#52 0x00007f6d67b3b7a6 in QV4::Function::call (this=<optimized out>, thisObject=<optimized out>, argv=<optimized out>, argc=<optimized out>, context=<optimized out>) at /usr/src/debug/qtdeclarative/src/qml/jsruntime/qv4function.cpp:69
#53 0x00007f6d67c8fb0d in QQmlJavaScriptExpression::evaluate (this=0x56236584b3a0, callData=0x7f6d4c9c04d0, isUndefined=0x0) at /usr/src/debug/qtdeclarative/src/qml/qml/qqmljavascriptexpression.cpp:212
#54 0x00007f6d67c52de1 in QQmlBoundSignalExpression::evaluate (this=<optimized out>, a=<optimized out>) at /usr/src/debug/qtdeclarative/src/qml/qml/qqmlboundsignal.cpp:224
#55 0x00007f6d67c53d5c in QQmlBoundSignal_callback (a=0x0, e=0x56236584b350) at ../../include/QtQml/5.15.4/QtQml/private/../../../../../../qtdeclarative/src/qml/qml/qqmlboundsignalexpressionpointer_p.h:69
#56 QQmlBoundSignal_callback (e=0x56236584b350, a=0x0) at /usr/src/debug/qtdeclarative/src/qml/qml/qqmlboundsignal.cpp:341
#57 0x00007f6d67c7656f in QQmlNotifier::emitNotify (endpoint=<optimized out>, a=0x0) at /usr/src/debug/qtdeclarative/src/qml/qml/qqmlnotifier.cpp:104
#58 0x00007f6d692be2bd in doActivate<false> (sender=0x562365840080, signal_index=64, argv=0x0) at kernel/qobject.cpp:3778
#59 0x00007f6d627c8a5a in QQuickAbstractButtonPrivate::handleRelease (this=0x562365840140, point=...) at /usr/src/debug/qtquickcontrols2/src/quicktemplates2/qquickabstractbutton.cpp:182
#60 0x00007f6d627e3ab9 in QQuickControl::mouseReleaseEvent (this=<optimized out>, event=0x7fff95b48c80) at /usr/src/debug/qtquickcontrols2/src/quicktemplates2/qquickcontrol.cpp:2151
#61 0x00007f6d6823c1c9 in QQuickItem::event (this=0x562365840080, ev=0x7fff95b48c80) at /usr/src/debug/qtdeclarative/src/quick/items/qquickitem.cpp:8221
#62 0x00007f6d69f78a7c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x562365840080, e=0x7fff95b48c80) at kernel/qapplication.cpp:3637
#63 0x00007f6d6928dff8 in QCoreApplication::notifyInternal2 (receiver=0x562365840080, event=0x7fff95b48c80) at kernel/qcoreapplication.cpp:1064
#64 0x00007f6d6824cd93 in QQuickWindowPrivate::deliverMouseEvent (this=this@entry=0x562364d52d00, pointerEvent=0x5623668b8940) at /usr/src/debug/qtdeclarative/src/quick/items/qquickwindow.cpp:2019
#65 0x00007f6d6824d7f2 in QQuickWindowPrivate::deliverPointerEvent (this=0x562364d52d00, event=0x5623668b8940) at /usr/src/debug/qtdeclarative/src/quick/items/qquickwindow.cpp:2611
#66 0x00007f6d69755c95 in QWindow::event (this=0x562364d2a870, ev=<optimized out>) at kernel/qwindow.cpp:2438
#67 0x00007f6d69f78a7c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x562364d2a870, e=0x7fff95b48c80) at kernel/qapplication.cpp:3637
#68 0x00007f6d6928dff8 in QCoreApplication::notifyInternal2 (receiver=0x562364d2a870, event=0x7fff95b48c80) at kernel/qcoreapplication.cpp:1064
#69 0x00007f6d67e18cae in QQuickWidget::mouseReleaseEvent (this=<optimized out>, e=0x7fff95b491f0) at /usr/src/debug/qtdeclarative/src/quickwidgets/qquickwidget.cpp:1416
#70 0x00007f6d69faf677 in QWidget::event (this=0x562364cf2e80, event=0x7fff95b491f0) at kernel/qwidget.cpp:8659
#71 0x00007f6d69f78a7c in QApplicationPrivate::notify_helper (this=this@entry=0x56236499cc50, receiver=receiver@entry=0x562364cf2e80, e=e@entry=0x7fff95b491f0) at kernel/qapplication.cpp:3637
#72 0x00007f6d69f7e289 in QApplication::notify (this=<optimized out>, receiver=<optimized out>, e=0x7fff95b491f0) at kernel/qapplication.cpp:3081
#73 0x00007f6d6928dff8 in QCoreApplication::notifyInternal2 (receiver=0x562364cf2e80, event=0x7fff95b491f0) at kernel/qcoreapplication.cpp:1064
#74 0x00007f6d69f7c287 in QApplicationPrivate::sendMouseEvent (receiver=0x562364cf2e80, event=0x7fff95b491f0, alienWidget=<optimized out>, nativeWidget=0x562364bc78c0, buttonDown=<optimized out>, lastMouseReceiver=..., spontaneous=true, onlyDispatchEnterLeave=false) at kernel/qapplication.cpp:2619
#75 0x00007f6d69fcd345 in QWidgetWindow::handleMouseEvent (this=0x562364d3ce90, event=0x7fff95b49550) at kernel/qwidgetwindow.cpp:683
#76 0x00007f6d69fcf0ee in QWidgetWindow::event (this=0x562364d3ce90, event=0x7fff95b49550) at kernel/qwidgetwindow.cpp:300
#77 0x00007f6d69f78a7c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x562364d3ce90, e=0x7fff95b49550) at kernel/qapplication.cpp:3637
#78 0x00007f6d6928dff8 in QCoreApplication::notifyInternal2 (receiver=0x562364d3ce90, event=0x7fff95b49550) at kernel/qcoreapplication.cpp:1064
#79 0x00007f6d6973efdc in QGuiApplicationPrivate::processMouseEvent (e=0x562365ef11d0) at kernel/qguiapplication.cpp:2282
#80 0x00007f6d69728945 in QWindowSystemInterface::sendWindowSystemEvents (flags=flags@entry=...) at kernel/qwindowsysteminterface.cpp:1169
#81 0x00007f6d63530df0 in xcbSourceDispatch (source=<optimized out>) at /usr/src/debug/qtbase/src/plugins/platforms/xcb/qxcbeventdispatcher.cpp:105
#82 0x00007f6d67069c6b in g_main_dispatch (context=0x7f6d5c005010) at ../glib/glib/gmain.c:3417
#83 g_main_context_dispatch (context=0x7f6d5c005010) at ../glib/glib/gmain.c:4135
#84 0x00007f6d670c0001 in g_main_context_iterate.constprop.0 (context=context@entry=0x7f6d5c005010, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/glib/gmain.c:4211
#85 0x00007f6d67067392 in g_main_context_iteration (context=0x7f6d5c005010, may_block=1) at ../glib/glib/gmain.c:4276
#86 0x00007f6d692d87bc in QEventDispatcherGlib::processEvents (this=0x562364a66850, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#87 0x00007f6d6928679c in QEventLoop::exec (this=0x7fff95b498f0, flags=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:69
#88 0x00007f6d692912a9 in QCoreApplication::exec () at ../../include/QtCore/../../src/corelib/global/qflags.h:121
#89 0x00007f6d69739fd2 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1867
#90 0x00007f6d69f76e8a in QApplication::exec () at kernel/qapplication.cpp:2829
#91 0x0000562363e7ebe8 in main (argc=<optimized out>, argv=0x7fff95b49a20) at /usr/src/debug/systemsettings-5.24.5/app/main.cpp:183


STEPS TO REPRODUCE
1. Change global shortcut in Custom shortcuts 
2. Press close on window
3. Press decline

OBSERVED RESULT
Systemsettings crashes

EXPECTED RESULT
Systemsettings doesn't crash

Operating System: Arch Linux
KDE Plasma Version: 5.24.5
KDE Frameworks Version: 5.94.0
Qt Version: 5.15.4
Kernel Version: 5.18.1-arch1-1 (64-bit)
Graphics Platform: X11
Processors: 4 × Intel® Core™ i3-2310M CPU @ 2.10GHz
Memory: 7,6 GiB of RAM
Graphics Processor: Mesa Intel® HD Graphics 3000