(In reply to Isaac Milarsky from comment #0)
> Created attachment 141039 [details]
> This is what the crash reporter gave me.
> 
> SUMMARY
> 
> 
> STEPS TO REPRODUCE
> 1. Boot computer with OpenSUSE Tumbleweed using KDE plasma to SDDM login
> screen.
> 2. Select the session as KDE with Wayland
> 3. Login like normal with SDDM
> 
> OBSERVED RESULT
> 
> Desktop is shown briefly before going to a black screen. No panels or
> widgets are present at any point but I do see desktop shortcuts before it
> goes black. After a few seconds the crash reporter launches.
> 
> 
> EXPECTED RESULT
> Successful Launch of a KDE Wayland session.
> 
> SOFTWARE/OS VERSIONS 
> Linux Version: 5.13.12-1-default(64-bit) 
> (available in About System)
> KDE Plasma Version: 5.22.4
> KDE Frameworks Version: 5.85.0
> Qt Version: 5.15.2
> 
> ADDITIONAL INFORMATION

Pasting inline":



Application: Plasma (plasmashell), signal: Segmentation fault
Content of s_kcrashErrorMessage: [Current thread is 1 (Thread 0x7fb0fe58b980 (LWP 2157))]
[KCrash Handler]
#6  0x00007fb1031ec05b in xcb_send_request_with_fds64 (c=0x0, flags=flags@entry=1, vector=vector@entry=0x7ffc54173300, req=req@entry=0x7fb1031f84a0 <xcb_req>, num_fds=num_fds@entry=0, fds=fds@entry=0x0) at /usr/src/debug/libxcb-1.14-1.6.x86_64/src/xcb_out.c:229
#7  0x00007fb1031ec81b in xcb_send_request64 (c=<optimized out>, flags=flags@entry=1, vector=vector@entry=0x7ffc54173300, req=req@entry=0x7fb1031f84a0 <xcb_req>) at /usr/src/debug/libxcb-1.14-1.6.x86_64/src/xcb_out.c:349
#8  0x00007fb1031ec829 in xcb_send_request (c=<optimized out>, flags=flags@entry=1, vector=vector@entry=0x7ffc54173300, req=req@entry=0x7fb1031f84a0 <xcb_req>) at /usr/src/debug/libxcb-1.14-1.6.x86_64/src/xcb_out.c:355
#9  0x00007fb1031edde4 in xcb_intern_atom (c=<optimized out>, only_if_exists=<optimized out>, name_len=<optimized out>, name=<optimized out>) at /usr/src/debug/libxcb-1.14-1.6.x86_64/src/xproto.c:3224
#10 0x00007fb1023d34d0 in Atoms::init() (this=this@entry=0x564286566840) at /usr/src/debug/kwindowsystem-5.85.0-1.1.x86_64/src/platforms/xcb/netwm.cpp:281
#11 0x00007fb1023d36b1 in Atoms::Atoms(xcb_connection_t*) (c=0x0, this=0x564286566840) at /usr/src/debug/kwindowsystem-5.85.0-1.1.x86_64/src/platforms/xcb/netwm.cpp:64
#12 atomsForConnection(xcb_connection_t*) (c=c@entry=0x0) at /usr/src/debug/kwindowsystem-5.85.0-1.1.x86_64/src/platforms/xcb/netwm.cpp:50
#13 0x00007fb1023da371 in NETRootInfo::NETRootInfo(xcb_connection_t*, QFlags<NET::Property>, QFlags<NET::Property2>, int, bool) (this=0x564286564dc0, connection=0x0, properties=..., properties2=..., screen=-1, doActivate=<optimized out>, this=<optimized out>, connection=<optimized out>, properties=..., properties2=..., screen=<optimized out>, doActivate=<optimized out>) at /usr/src/debug/kwindowsystem-5.85.0-1.1.x86_64/src/platforms/xcb/netwm.cpp:496
#14 0x00007fb0bff69ae5 in VirtualDesktopBar::VirtualDesktopBar(QObject*) () at /usr/lib64/qt5/qml/org/kde/plasma/virtualdesktopbar/libvirtualdesktopbar.so
#15 0x00007fb0bff7141b in void QQmlPrivate::createInto<VirtualDesktopBar>(void*) () at /usr/lib64/qt5/qml/org/kde/plasma/virtualdesktopbar/libvirtualdesktopbar.so
#16 0x00007fb1026d479a in QQmlType::create(QObject**, void**, unsigned long) const (this=this@entry=0x7ffc54173a18, out=out@entry=0x7ffc54173a10, memory=memory@entry=0x7ffc54173a20, additionalMemory=additionalMemory@entry=144) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmltype.cpp:499
#17 0x00007fb10272552b in QQmlObjectCreator::createInstance(int, QObject*, bool) (this=0x56428653d150, index=5, parent=0x564286538d90, isContextObject=<optimized out>) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlobjectcreator.cpp:1189
#18 0x00007fb102727a92 in QQmlObjectCreator::setPropertyBinding(QQmlPropertyData const*, QV4::CompiledData::Binding const*) (this=0x56428653d150, bindingProperty=0x7fb0dc0a0eb8, binding=0x7fb0bff7a9f4) at /usr/include/qt5/QtCore/qendian.h:290
#19 0x00007fb10272801f in QQmlObjectCreator::setupBindings(bool) (this=0x56428653d150, applyDeferredBindings=false) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlobjectcreator.cpp:798
#20 0x00007fb102724013 in QQmlObjectCreator::populateInstance(int, QObject*, QObject*, QQmlPropertyData const*) (this=this@entry=0x56428653d150, index=-1, index@entry=0, instance=0x0, bindingTarget=0x0, valueTypeProperty=valueTypeProperty@entry=0x0) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlobjectcreator.cpp:1555
#21 0x00007fb102725004 in QQmlObjectCreator::createInstance(int, QObject*, bool) (this=<optimized out>, index=<optimized out>, parent=<optimized out>, isContextObject=<optimized out>) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlobjectcreator.cpp:1348
#22 0x00007fb102725c4f in QQmlObjectCreator::create(int, QObject*, QQmlInstantiationInterrupt*, int) (this=0x56428653d150, subComponentIndex=<optimized out>, parent=parent@entry=0x0, interrupt=interrupt@entry=0x7ffc541742d0, flags=flags@entry=1) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlobjectcreator.cpp:204
#23 0x00007fb1026b77c1 in QQmlIncubatorPrivate::incubate(QQmlInstantiationInterrupt&) (this=0x564285985860, i=...) at /usr/include/qt5/QtCore/qscopedpointer.h:116
#24 0x00007fb1026b80bd in QQmlEnginePrivate::incubate(QQmlIncubator&, QQmlContextData*) (this=0x564285735030, i=<optimized out>, forContext=<optimized out>) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlincubator.cpp:89
#25 0x00007fb1026b19fb in QQmlComponent::create(QQmlIncubator&, QQmlContext*, QQmlContext*) (this=<optimized out>, incubator=..., context=<optimized out>, forContext=<optimized out>) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/qml/qml/qqmlcomponent.cpp:1178
#26 0x00007fb1030c18da in KDeclarative::QmlObject::completeInitialization(QHash<QString, QVariant> const&) (initialProperties=<optimized out>, this=0x56428598c750) at /usr/src/debug/kdeclarative-5.85.0-1.1.x86_64/src/kdeclarative/qmlobject.cpp:307
#27 KDeclarative::QmlObject::completeInitialization(QHash<QString, QVariant> const&) (this=0x56428598c750, initialProperties=<optimized out>) at /usr/src/debug/kdeclarative-5.85.0-1.1.x86_64/src/kdeclarative/qmlobject.cpp:289
#28 0x00007fb1033949eb in PlasmaQuick::AppletQuickItem::init() (this=this@entry=0x56428598c8a0) at /usr/src/debug/plasma-framework-5.85.0-2.1.x86_64/src/plasmaquick/appletquickitem.cpp:649
#29 0x00007fb0f114d802 in AppletInterface::init() (this=0x56428598c8a0) at /usr/src/debug/plasma-framework-5.85.0-2.1.x86_64/src/scriptengines/qml/plasmoid/appletinterface.cpp:141
#30 0x00007fb103391e91 in PlasmaQuick::AppletQuickItem::itemChange(QQuickItem::ItemChange, QQuickItem::ItemChangeData const&) (this=0x56428598c8a0, change=QQuickItem::ItemSceneChange, value=...) at /usr/src/debug/plasma-framework-5.85.0-2.1.x86_64/src/plasmaquick/appletquickitem.cpp:927
#31 0x00007fb102bd13ab in QQuickItemPrivate::refWindow(QQuickWindow*) (this=0x56428598c950, c=0x564285b4b870) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/quick/items/qquickitem.cpp:3003
#32 0x00007fb102bd1369 in QQuickItemPrivate::refWindow(QQuickWindow*) (this=0x5642858d4160, c=0x564285b4b870) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/quick/items/qquickitem.cpp:2996
#33 0x00007fb102bd1770 in QQuickItem::setParentItem(QQuickItem*) (this=this@entry=0x564285913000, parentItem=<optimized out>) at /usr/src/debug/libqt5-qtdeclarative-5.15.2+kde29-1.3.x86_64/src/quick/items/qquickitem.cpp:2716
#34 0x00007fb103399d1d in PlasmaQuick::ContainmentViewPrivate::setContainment(Plasma::Containment*) (this=0x56428592a3f0, cont=<optimized out>) at /usr/src/debug/plasma-framework-5.85.0-2.1.x86_64/src/plasmaquick/containmentview.cpp:122
#35 0x000056428524ab97 in ShellCorona::createWaitingPanels() (this=<optimized out>) at /usr/src/debug/plasma5-workspace-5.22.4-1.4.x86_64/shell/shellcorona.cpp:1335
#36 0x00007fb1010f9fd3 in QtPrivate::QSlotObjectBase::call(QObject*, void**) (a=0x7ffc54174b40, r=0x564285311020, this=0x564285634060) at ../../include/QtCore/../../src/corelib/kernel/qobjectdefs_impl.h:398
#37 doActivate<false>(QObject*, int, void**) (sender=0x5642853110d8, signal_index=3, argv=0x7ffc54174b40) at kernel/qobject.cpp:3886
#38 0x00007fb1010f349f in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) (sender=<optimized out>, m=m@entry=0x7fb101393be0, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffc54174b40) at kernel/qobject.cpp:3946
#39 0x00007fb1010fde8a in QTimer::timeout(QTimer::QPrivateSignal) (this=<optimized out>, _t1=...) at .moc/moc_qtimer.cpp:205
#40 0x00007fb1010efe9f in QObject::event(QEvent*) (this=0x5642853110d8, e=0x7ffc54174cc0) at kernel/qobject.cpp:1336
#41 0x00007fb101e55a7f in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=<optimized out>, receiver=0x5642853110d8, e=0x7ffc54174cc0) at kernel/qapplication.cpp:3632
#42 0x00007fb1010c398a in QCoreApplication::notifyInternal2(QObject*, QEvent*) (receiver=0x5642853110d8, event=0x7ffc54174cc0) at kernel/qcoreapplication.cpp:1064
#43 0x00007fb10111a1fb in QTimerInfoList::activateTimers() (this=this@entry=0x564285344270) at kernel/qtimerinfo_unix.cpp:643
#44 0x00007fb10111aaa4 in timerSourceDispatch(GSource*, GSourceFunc, gpointer) (source=source@entry=0x564285344210) at kernel/qeventdispatcher_glib.cpp:183
#45 0x00007fb0ff3e480f in g_main_dispatch (context=0x56428535d4b0) at ../glib/gmain.c:3337
#46 g_main_context_dispatch (context=0x56428535d4b0) at ../glib/gmain.c:4055
#47 0x00007fb0ff3e4b98 in g_main_context_iterate (context=context@entry=0x56428535d4b0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4131
#48 0x00007fb0ff3e4c4f in g_main_context_iteration (context=0x56428535d4b0, may_block=1) at ../glib/gmain.c:4196
#49 0x00007fb10111ae64 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x564285383c00, flags=...) at kernel/qeventdispatcher_glib.cpp:423
#50 0x00007fb1010c238b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7ffc54174f00, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:69
#51 0x00007fb1010ca670 in QCoreApplication::exec() () at ../../include/QtCore/../../src/corelib/global/qflags.h:121
#52 0x00007fb10150e19c in QGuiApplication::exec() () at kernel/qguiapplication.cpp:1867
#53 0x00007fb101e559f5 in QApplication::exec() () at kernel/qapplication.cpp:2824
#54 0x000056428522a479 in main(int, char**) (argc=<optimized out>, argv=0x7ffc541750f0) at /usr/src/debug/plasma5-workspace-5.22.4-1.4.x86_64/shell/main.cpp:254
[Inferior 1 (process 2157) detached]

Created attachment 142387 [details]
New crash information added by DrKonqi

plasmashell (5.22.5) using Qt 5.15.3

- Unusual behavior I noticed:
The desktop wallpapers gets shown for an instant, without any bar or widget, then the desktop goes black.
Windows like that of the Nextcloud syncing client appear and stays on the screen (with Xorg it doesn't appear unless I click its icon in the system tray).
Windows get open normally, like when I click on the link in the bug report window to register on the KDE bugtracker and Firefox opens in a working window.

-- Backtrace (Reduced):
#4  0x00007f56c91966f8 in xcb_send_request_with_fds64 (c=0x0, flags=flags@entry=1, vector=vector@entry=0x7ffd8efed900, req=req@entry=0x7f56c91aaee0 <xcb_req>, num_fds=num_fds@entry=0, fds=fds@entry=0x0) at ../../src/xcb_out.c:223
#5  0x00007f56c9196c3f in xcb_send_request64 (c=<optimized out>, flags=flags@entry=1, vector=vector@entry=0x7ffd8efed900, req=req@entry=0x7f56c91aaee0 <xcb_req>) at ../../src/xcb_out.c:349
#6  0x00007f56c9196c4d in xcb_send_request (c=<optimized out>, flags=flags@entry=1, vector=vector@entry=0x7ffd8efed900, req=req@entry=0x7f56c91aaee0 <xcb_req>) at ../../src/xcb_out.c:355
#7  0x00007f56c919d668 in xcb_intern_atom (c=<optimized out>, only_if_exists=only_if_exists@entry=0 '\000', name_len=<optimized out>, name=name@entry=0x7f56c8295320 "UTF8_STRING") at xproto.c:3224
#8  0x00007f56c8283360 in Atoms::init (this=this@entry=0x562ae6c3dd00) at ./src/platforms/xcb/netwm.cpp:281

*** Bug 442535 has been marked as a duplicate of this bug. ***

*** Bug 440378 has been marked as a duplicate of this bug. ***

VirtualDesktopBar appears to be from an external program: I think https://github.com/wsdfhjxc/virtual-desktop-bar

This is making unconditional X calls. Please can you file a bug there.

Seems there are bug reports there already.

https://github.com/wsdfhjxc/virtual-desktop-bar/issues/38