#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0)
    at pthread_kill.c:44
#1  0x00007fb9c0aebec3 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at pthread_kill.c:78
#2  0x00007fb9c0a9ba76 in __GI_raise (sig=6) at ../sysdeps/posix/raise.c:26
#3  0x00007fb9c3f258fd in KCrash::defaultCrashHandler(int) (sig=6) at /home/nico/kde6/src/kcrash/src/kcrash.cpp:612
#4  0x00007fb9c0a9bb20 in <signal handler called> () at /lib64/libc.so.6
#5  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0)
    at pthread_kill.c:44
#6  0x00007fb9c0aebec3 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at pthread_kill.c:78
#7  0x00007fb9c0a9ba76 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#8  0x00007fb9c0a857fc in __GI_abort () at abort.c:79
#9  0x00007fb9c00a2b97 in __gnu_cxx::__verbose_terminate_handler() ()
    at ../../../../libstdc++-v3/libsupc++/vterminate.cc:95
#10 0x00007fb9c00ae48c in __cxxabiv1::__terminate(void (*)()) (handler=<optimized out>)
    at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:48
#11 0x00007fb9c00ae4f7 in std::terminate() () at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:58
#12 0x00007fb9c00ae758 in __cxxabiv1::__cxa_throw(void*, std::type_info*, void (*)(void*))
    (obj=<optimized out>, tinfo=0x7fb9c0224cd8 <typeinfo for std::bad_alloc>, dest=0x7fb9c00acb30 <std::bad_alloc::~bad_alloc()>) at ../../../../libstdc++-v3/libsupc++/eh_throw.cc:98
#13 0x00007fb9c00a27a0 in operator new(unsigned long) (sz=633318697598984)
    at ../../../../libstdc++-v3/libsupc++/new_op.cc:54
#14 0x00007fb9c00aec59 in operator new[](unsigned long) (sz=<optimized out>)
    at ../../../../libstdc++-v3/libsupc++/new_opv.cc:32
#15 0x00007fb9c034ea92 in QHashPrivate::Data<QHashPrivate::Node<long long, MessageList::Core::MessageItem*> >::Data(unsigned long) (reserve=<optimized out>, this=0x1989fe0) at /usr/include/qt6/QtCore/qhash.h:536
#16 QHashPrivate::Data<QHashPrivate::Node<long long, MessageList::Core::MessageItem*> >::detached(QHashPrivate::Data<QHashPrivate::Node<long long, MessageList::Core::MessageItem*> >*, unsigned long)
    (size=<optimized out>, d=<optimized out>) at /usr/include/qt6/QtCore/qhash.h:583
#17 QHash<long long, MessageList::Core::MessageItem*>::reserve(long long) (size=<optimized out>, this=0xde4290)
    at /usr/include/qt6/QtCore/qhash.h:931
#18 QHash<long long, MessageList::Core::MessageItem*>::reserve(long long) (this=0xde4290, size=<optimized out>)
    at /usr/include/qt6/QtCore/qhash.h:923
#19 0x00007fb9c034cec8 in MessageList::Core::ThreadingCache::load(QString const&, MessageList::Core::Aggregation const*) (this=this@entry=0xde4288, id=..., aggregation=aggregation@entry=0xc0b020)
    at /home/nico/kde6/src/messagelib/messagelist/src/core/threadingcache.cpp:113
#20 0x00007fb9c03285dd in MessageList::Core::Model::setStorageModel(MessageList::Core::StorageModel*, MessageList::Core::PreSelectionMode)
     (this=0xd75b80, storageModel=storageModel@entry=0x1127040, preSelectionMode=preSelectionMode@entry=MessageList::Core::PreSelectLastSelected)
    at /home/nico/kde6/src/messagelib/messagelist/src/core/model.cpp:783
#21 0x00007fb9c0354fb5 in MessageList::Core::View::setStorageModel(MessageList::Core::StorageModel*, MessageList::Core::PreSelectionMode)
     (this=0xd89880, storageModel=storageModel@entry=0x1127040, preSelectionMode=preSelectionMode@entry=MessageList::Core::PreSelectLastSelected) at /home/nico/kde6/src/messagelib/messagelist/src/core/view.cpp:282
#22 0x00007fb9c036247a in MessageList::Core::Widget::setStorageModel(MessageList::Core::StorageModel*, MessageList::Core::PreSelectionMode)
     (this=0xdd1e90, storageModel=0x1127040, preSelectionMode=MessageList::Core::PreSelectLastSelected)
    at /home/nico/kde6/src/messagelib/messagelist/src/core/widgetbase.cpp:367
#23 0x00007fb9c038b993 in MessageList::Pane::setCurrentFolder(Akonadi::Collection const&, QModelIndex const&, bool, MessageList::Core::PreSelectionMode, QString const&)
     (this=0xc80be0, collection=..., etmIndex=..., preSelectionMode=MessageList::Core::PreSelectLastSelected, overrideLabel=...) at /home/nico/kde6/src/messagelib/messagelist/src/pane.cpp:790
#24 0x00007fb9cd853254 in KMMainWidget::slotShowSelectedFolderInPane() (this=0xbf6400)
    at /home/nico/kde6/src/kmail/src/kmmainwidget.cpp:559
#25 0x00007fb9c05ba370 in QObject::event(QEvent*) (this=0xbf6400, e=0xf06ed0)
    at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/kernel/qobject.cpp:1378
--Type <RET> for more, q to quit, c to continue without paging--
#26 0x00007fb9c19baa65 in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0xbf6400, e=0xf06ed0) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/widgets/kernel/qapplication.cpp:3315
#27 0x00007fb9c0568068 in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0xbf6400, event=0xf06ed0) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/kernel/qcoreapplication.cpp:1026
#28 0x00007fb9c056f170 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (receiver=0x0, event_type=0, data=0x944a40) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/kernel/qcoreapplication.cpp:1804
#29 0x00007fb9c0823957 in postEventSourceDispatch(GSource*, GSourceFunc, gpointer) (s=0x967ee0) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/kernel/qeventdispatcher_glib.cpp:243
#30 0x00007fb9bdaa4c7f in g_main_dispatch (context=0x98ead0) at ../glib/gmain.c:3454
#31 g_main_context_dispatch (context=0x98ead0) at ../glib/gmain.c:4172
#32 0x00007fb9bdafb118 in g_main_context_iterate.constprop.0 (context=0x98ead0, block=1, dispatch=1, self=<optimized out>) at ../glib/gmain.c:4248
#33 0x00007fb9bdaa1f00 in g_main_context_iteration (context=0x98ead0, may_block=1) at ../glib/gmain.c:4313
#34 0x00007fb9c0823220 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x903a30, flags=...) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/kernel/qeventdispatcher_glib.cpp:393
#35 0x00007fb9c057465b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7ffede081340, flags=..., flags@entry=...) at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/global/qflags.h:34
#36 0x00007fb9c0570528 in QCoreApplication::exec() () at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/corelib/global/qflags.h:74
#37 0x00007fb9c0feefc0 in QGuiApplication::exec() () at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/gui/kernel/qguiapplication.cpp:1859
#38 0x00007fb9c19ba9d9 in QApplication::exec() () at /usr/src/debug/qt6-qtbase-6.4.2-4.fc37.x86_64/src/widgets/kernel/qapplication.cpp:2595
#39 0x00000000004055a5 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at /home/nico/kde6/src/kmail/src/main.cpp:185

PIM master, Qt 6.4.2