SUMMARY
I recorded my screen three times in sequence with Kooha installed from flathub.org.
xdg-desktop-portal-kde crashed after finishing the last recording.

Operating System: KDE neon Unstable Edition
KDE Plasma Version: 5.27.80
KDE Frameworks Version: 5.240.0
Qt Version: 6.6.0
Graphics Platform: Wayland


Thread 5 (Thread 0x7f87595ff640 (LWP 12065)):
#0  0x00007f875d518d7f in __GI___poll (fds=0x55b3f055c330, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f875cc8a1f6 in g_main_context_poll (priority=<optimized out>, n_fds=2, fds=0x55b3f055c330, timeout=<optimized out>, context=0x7f8754001d20) at ../../../glib/gmain.c:4518
#2  g_main_context_iterate.constprop.0 (context=context@entry=0x7f8754001d20, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../../../glib/gmain.c:4208
#3  0x00007f875cc323e3 in g_main_context_iteration (context=0x7f8754001d20, may_block=1) at ../../../glib/gmain.c:4278
#4  0x00007f875dfb57fe in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#5  0x00007f875dd66df3 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#6  0x00007f875de44030 in QThread::exec() () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#7  0x00007f875f44dd5e in ?? () from /lib/x86_64-linux-gnu/libQt6DBus.so.6
#8  0x00007f875deceb5c in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#9  0x00007f875d494b43 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#10 0x00007f875d526a00 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Thread 4 (Thread 0x7f8750fff640 (LWP 12068)):
#0  __futex_abstimed_wait_common64 (private=0, cancel=true, abstime=0x0, op=393, expected=0, futex_word=0x55b3f0611638) at ./nptl/futex-internal.c:57
#1  __futex_abstimed_wait_common (cancel=true, private=0, abstime=0x0, clockid=0, expected=0, futex_word=0x55b3f0611638) at ./nptl/futex-internal.c:87
#2  __GI___futex_abstimed_wait_cancelable64 (futex_word=futex_word@entry=0x55b3f0611638, expected=expected@entry=0, clockid=clockid@entry=0, abstime=abstime@entry=0x0, private=private@entry=0) at ./nptl/futex-internal.c:139
#3  0x00007f875d493ac1 in __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55b3f06115e8, cond=0x55b3f0611610) at ./nptl/pthread_cond_wait.c:503
#4  ___pthread_cond_wait (cond=0x55b3f0611610, mutex=0x55b3f06115e8) at ./nptl/pthread_cond_wait.c:627
#5  0x00007f875110f89d in cnd_wait (cond=<optimized out>, mtx=<optimized out>) at ../src/c11/impl/threads_posix.c:135
#6  0x00007f87510bfb0b in util_queue_thread_func (input=input@entry=0x55b3f060a5e0) at ../src/util/u_queue.c:290
#7  0x00007f875110f7cb in impl_thrd_routine (p=<optimized out>) at ../src/c11/impl/threads_posix.c:67
#8  0x00007f875d494b43 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#9  0x00007f875d526a00 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Thread 3 (Thread 0x7f8753fff640 (LWP 12066)):
#0  __futex_abstimed_wait_common64 (private=0, cancel=true, abstime=0x0, op=393, expected=0, futex_word=0x55b3f05991a4) at ./nptl/futex-internal.c:57
#1  __futex_abstimed_wait_common (cancel=true, private=0, abstime=0x0, clockid=0, expected=0, futex_word=0x55b3f05991a4) at ./nptl/futex-internal.c:87
#2  __GI___futex_abstimed_wait_cancelable64 (futex_word=futex_word@entry=0x55b3f05991a4, expected=expected@entry=0, clockid=clockid@entry=0, abstime=abstime@entry=0x0, private=private@entry=0) at ./nptl/futex-internal.c:139
#3  0x00007f875d493ac1 in __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x55b3f0599150, cond=0x55b3f0599178) at ./nptl/pthread_cond_wait.c:503
#4  ___pthread_cond_wait (cond=0x55b3f0599178, mutex=0x55b3f0599150) at ./nptl/pthread_cond_wait.c:627
#5  0x00007f875ded6a1b in QWaitCondition::wait(QMutex*, QDeadlineTimer) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#6  0x00007f875f2cc807 in ?? () from /lib/x86_64-linux-gnu/libQt6WaylandClient.so.6
#7  0x00007f875deceb5c in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#8  0x00007f875d494b43 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#9  0x00007f875d526a00 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Thread 2 (Thread 0x7f87537fe640 (LWP 12067)):
#0  0x00007f875d518d7f in __GI___poll (fds=0x7f87537fda00, nfds=2, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f875f2cc876 in ?? () from /lib/x86_64-linux-gnu/libQt6WaylandClient.so.6
#2  0x00007f875deceb5c in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#3  0x00007f875d494b43 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#4  0x00007f875d526a00 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Thread 1 (Thread 0x7f8759e6dfc0 (LWP 12064)):
#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=140219305615296) at ./nptl/pthread_kill.c:44
#1  __pthread_kill_internal (signo=6, threadid=140219305615296) at ./nptl/pthread_kill.c:78
#2  __GI___pthread_kill (threadid=140219305615296, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#3  0x00007f875d442476 in __GI_raise (sig=6) at ../sysdeps/posix/raise.c:26
#4  0x00007f875f18e5ff in KCrash::defaultCrashHandler(int) () from /lib/x86_64-linux-gnu/libKF6Crash.so.6
#5  <signal handler called>
#6  __pthread_kill_implementation (no_tid=0, signo=6, threadid=140219305615296) at ./nptl/pthread_kill.c:44
#7  __pthread_kill_internal (signo=6, threadid=140219305615296) at ./nptl/pthread_kill.c:78
#8  __GI___pthread_kill (threadid=140219305615296, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#9  0x00007f875d442476 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#10 0x00007f875d4287f3 in __GI_abort () at ./stdlib/abort.c:79
#11 0x00007f875dcb9172 in qAbort() () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#12 0x00007f875dcba0f7 in QMessageLogger::fatal(char const*, ...) const () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#13 0x00007f875dcb90c3 in qt_assert(char const*, char const*, int) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#14 0x000055b3ef53983e in NotificationPortal::notificationClosed (this=0x55b3f0671050) at ./src/notification.cpp:187
#15 0x00007f875ddb0757 in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#16 0x00007f8760ad32e7 in KNotification::close() () from /lib/x86_64-linux-gnu/libKF6Notifications.so.6
#17 0x00007f875ddb0757 in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#18 0x00007f8760ae9d74 in ?? () from /lib/x86_64-linux-gnu/libKF6Notifications.so.6
#19 0x00007f875ddb0757 in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#20 0x00007f8760b0d19f in ?? () from /lib/x86_64-linux-gnu/libKF6Notifications.so.6
#21 0x00007f8760b0d600 in ?? () from /lib/x86_64-linux-gnu/libKF6Notifications.so.6
#22 0x00007f875f463190 in ?? () from /lib/x86_64-linux-gnu/libQt6DBus.so.6
#23 0x00007f875dda777c in QObject::event(QEvent*) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#24 0x00007f875eb89596 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt6Widgets.so.6
#25 0x00007f875dd5a128 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#26 0x00007f875dd5e0f8 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#27 0x00007f875dfb5f97 in ?? () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#28 0x00007f875cc34d3b in g_main_dispatch (context=0x7f8754005040) at ../../../glib/gmain.c:3419
#29 g_main_context_dispatch (context=0x7f8754005040) at ../../../glib/gmain.c:4137
#30 0x00007f875cc8a258 in g_main_context_iterate.constprop.0 (context=context@entry=0x7f8754005040, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../../../glib/gmain.c:4213
#31 0x00007f875cc323e3 in g_main_context_iteration (context=0x7f8754005040, may_block=1) at ../../../glib/gmain.c:4278
#32 0x00007f875dfb57fe in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#33 0x00007f875dd66df3 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#34 0x00007f875dd62d06 in QCoreApplication::exec() () from /lib/x86_64-linux-gnu/libQt6Core.so.6
#35 0x000055b3ef53f8c5 in main (argc=<optimized out>, argv=<optimized out>) at ./src/xdg-desktop-portal-kde.cpp:47