SUMMARY
kwin_wayland crashes while casting one of my screens using WebRTC/Pipewire/xdg-desktop-portal in Chromium. I can reproduce the crash by simply interacting with the UI in many ways, e.g. opening a new tab in my browser, browsing around in Dolphin, etc.

This only seems to occur with Chromium, and not with Firefox.

STEPS TO REPRODUCE
1. Open Chromium
2. Share your screen using WebRTC, e.g. on https://www.webrtc-experiment.com/Pluginfree-Screen-Sharing/
3. Use your desktop.

OBSERVED RESULT
KWin crashes.

EXPECTED RESULT
No crashes.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.23.4
KDE Frameworks Version: 5.89.0
Qt Version: 5.15.2
Kernel Version: 5.15.7-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 5600X 6-Core Processor
Memory: 15,5 GiB of RAM
Graphics Processor: AMD Radeon RX 480 Graphics

ADDITIONAL INFORMATION
Backtrace:

[Current thread is 1 (Thread 0x7fe9457510c0 (LWP 38540))]
(gdb) bt
#0  0x00007fe94ce89580 in  () at /usr/lib/libkwinglutils.so.13
#1  0x00007fe94ce8a56d in KWin::GLVertexBuffer::setData(int, int, float const*, float const*) () at /usr/lib/libkwinglutils.so.13
#2  0x00007fe94ce84e18 in KWin::GLTexture::render(QRegion const&, QRect const&, bool) () at /usr/lib/libkwinglutils.so.13
#3  0x000055db5d5bd113 in  ()
#4  0x000055db5d5bd385 in  ()
#5  0x00007fe94b9137cb in  () at /usr/lib/libQt5Core.so.5
#6  0x00007fe94d0bb6b8 in KWin::Cursors::positionChanged(KWin::Cursor*, QPoint const&) () at /usr/lib/libkwin.so.5
#7  0x00007fe94b9137cb in  () at /usr/lib/libQt5Core.so.5
#8  0x00007fe94d0bb4f3 in KWin::Cursor::posChanged(QPoint const&) () at /usr/lib/libkwin.so.5
#9  0x00007fe94d1aa091 in  () at /usr/lib/libkwin.so.5
#10 0x00007fe94b9137cb in  () at /usr/lib/libQt5Core.so.5
#11 0x00007fe94d0bbd83 in KWin::InputRedirection::globalPointerChanged(QPointF const&) () at /usr/lib/libkwin.so.5
#12 0x00007fe94d1acfb8 in KWin::PointerInputRedirection::updatePosition(QPointF const&) () at /usr/lib/libkwin.so.5
#13 0x00007fe94d1ad90d in KWin::PointerInputRedirection::processMotion(QPointF const&, QSizeF const&, QSizeF const&, unsigned int, unsigned long long, KWin::LibInput::Device*) () at /usr/lib/libkwin.so.5
#14 0x00007fe94d15dd15 in  () at /usr/lib/libkwin.so.5
#15 0x00007fe94b9137cb in  () at /usr/lib/libQt5Core.so.5
#16 0x00007fe94d0bcc0a in KWin::LibInput::Connection::pointerMotion(QSizeF const&, QSizeF const&, unsigned int, unsigned long long, KWin::LibInput::Device*) () at /usr/lib/libkwin.so.5
#17 0x00007fe94d18c7ca in KWin::LibInput::Connection::processEvents() () at /usr/lib/libkwin.so.5
#18 0x00007fe94b90956f in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5
#19 0x00007fe94c5bcd62 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#20 0x00007fe94b8dc41a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#21 0x00007fe94b8df519 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/libQt5Core.so.5
#22 0x00007fe94b9324ec in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#23 0x000055db5d5f2d7e in  ()
#24 0x00007fe94b8dad8c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#25 0x00007fe94b8e32f4 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#26 0x000055db5d58f8cb in  ()
#27 0x00007fe94b036b25 in __libc_start_main () at /usr/lib/libc.so.6
#28 0x000055db5d5902ce in  ()