Application: kwin_x11 (5.13.4)

Qt Version: 5.11.1
Frameworks Version: 5.49.0
Operating System: Linux 4.18.3-arch1-1-ARCH x86_64
Distribution (Platform): Archlinux Packages

-- Information about the crash:
- What I was doing when the application crashed: I opened Steam native

- Unusual behavior I noticed: The bar went black and I noticed that the application launcher turned into a black square that I can also see in fullscreen games

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin_x11), signal: Aborted
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fd768f206c0 (LWP 719))]

Thread 7 (Thread 0x7fd74d824700 (LWP 1005)):
#0  0x00007fd778efdca6 in ppoll () at /usr/lib/libc.so.6
#1  0x00007fd7774e337b in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007fd7774e486b in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007fd777492dac in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007fd7772dbf59 in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007fd772f580d9 in  () at /usr/lib/libQt5Qml.so.5
#6  0x00007fd7772e6005 in  () at /usr/lib/libQt5Core.so.5
#7  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 6 (Thread 0x7fd74d023700 (LWP 784)):
#0  0x00007fd773d23afc in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007fd7765feaac in  () at /usr/lib/libQt5Script.so.5
#2  0x00007fd7765feac9 in  () at /usr/lib/libQt5Script.so.5
#3  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 5 (Thread 0x7fd74e025700 (LWP 781)):
#0  0x00007fd773d23afc in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1  0x00007fd74ebef264 in  () at /usr/lib/dri/i965_dri.so
#2  0x00007fd74ebeef58 in  () at /usr/lib/dri/i965_dri.so
#3  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#4  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 4 (Thread 0x7fd75dcf8700 (LWP 770)):
#0  0x00007fd7774e3228 in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#1  0x00007fd7774e486b in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#2  0x00007fd777492dac in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007fd7772dbf59 in QThread::exec() () at /usr/lib/libQt5Core.so.5
#4  0x00007fd772f580d9 in  () at /usr/lib/libQt5Qml.so.5
#5  0x00007fd7772e6005 in  () at /usr/lib/libQt5Core.so.5
#6  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#7  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 3 (Thread 0x7fd75f9a6700 (LWP 757)):
#0  0x00007fd778efdca6 in ppoll () at /usr/lib/libc.so.6
#1  0x00007fd7774e337b in qt_safe_poll(pollfd*, unsigned long, timespec const*) () at /usr/lib/libQt5Core.so.5
#2  0x00007fd7774e486b in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#3  0x00007fd777492dac in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4  0x00007fd7772dbf59 in QThread::exec() () at /usr/lib/libQt5Core.so.5
#5  0x00007fd772a34ba6 in  () at /usr/lib/libQt5DBus.so.5
#6  0x00007fd7772e6005 in  () at /usr/lib/libQt5Core.so.5
#7  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#8  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7fd767739700 (LWP 720)):
#0  0x00007fd778efdbb1 in poll () at /usr/lib/libc.so.6
#1  0x00007fd778612180 in  () at /usr/lib/libxcb.so.1
#2  0x00007fd778613e4b in xcb_wait_for_event () at /usr/lib/libxcb.so.1
#3  0x00007fd768828e1a in  () at /usr/lib/libQt5XcbQpa.so.5
#4  0x00007fd7772e6005 in  () at /usr/lib/libQt5Core.so.5
#5  0x00007fd773d1da9d in start_thread () at /usr/lib/libpthread.so.0
#6  0x00007fd778f08a43 in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7fd768f206c0 (LWP 719)):
[KCrash Handler]
#6  0x00007fd778e44d7f in raise () at /usr/lib/libc.so.6
#7  0x00007fd778e2f672 in abort () at /usr/lib/libc.so.6
#8  0x00007fd778e2f548 in _nl_load_domain.cold.0 () at /usr/lib/libc.so.6
#9  0x00007fd778e3d396 in  () at /usr/lib/libc.so.6
#10 0x00007fd773622f50 in  () at /usr/lib/libepoxy.so.0
#11 0x00007fd7735c31c0 in  () at /usr/lib/libepoxy.so.0
#12 0x00007fd7735ca1aa in  () at /usr/lib/libepoxy.so.0
#13 0x00007fd7738a392c in KWin::GLRenderTarget::~GLRenderTarget() () at /usr/lib/libkwinglutils.so.11
#14 0x00007fd776b7669e in  () at /usr/lib/libkwin4_effect_builtins.so.1
#15 0x00007fd776b78e17 in  () at /usr/lib/libkwin4_effect_builtins.so.1
#16 0x00007fd776b79019 in  () at /usr/lib/libkwin4_effect_builtins.so.1
#17 0x00007fd778a9223a in KWin::EffectsHandlerImpl::unloadAllEffects() () at /usr/lib/libkwin.so.5
#18 0x00007fd778a922d8 in KWin::EffectsHandlerImpl::~EffectsHandlerImpl() () at /usr/lib/libkwin.so.5
#19 0x00007fd75fbd6ff9 in  () at /usr/lib/qt/plugins/org.kde.kwin.platforms/KWinX11Platform.so
#20 0x00007fd75fbd70c9 in  () at /usr/lib/qt/plugins/org.kde.kwin.platforms/KWinX11Platform.so
#21 0x00007fd778a72d2f in  () at /usr/lib/libkwin.so.5
#22 0x00007fd778a732ed in KWin::Compositor::suspend(KWin::Compositor::SuspendReason) () at /usr/lib/libkwin.so.5
#23 0x00007fd7774be832 in QObject::event(QEvent*) () at /usr/lib/libQt5Core.so.5
#24 0x00007fd777e0ee14 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#25 0x00007fd777e166e1 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/libQt5Widgets.so.5
#26 0x00007fd777494119 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/libQt5Core.so.5
#27 0x00007fd7774971ac in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/libQt5Core.so.5
#28 0x00007fd7774e46dd in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#29 0x00007fd7688be5ce in  () at /usr/lib/libQt5XcbQpa.so.5
#30 0x00007fd777492dac in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#31 0x00007fd77749b0a6 in QCoreApplication::exec() () at /usr/lib/libQt5Core.so.5
#32 0x00007fd778fd9b56 in kdemain () at /usr/lib/libkdeinit5_kwin_x11.so
#33 0x00007fd778e31223 in __libc_start_main () at /usr/lib/libc.so.6
#34 0x000055e42b24a75a in _start ()

Reported using DrKonqi