#4 0x00007f63e1234ab9 in KWin::EffectQuickView::EffectQuickView(QObject*, QWindow*, KWin::EffectQuickView::ExportMode) () at /usr/lib64/libkwineffects.so.13#5 0x00007f63e147391f in () at /usr/lib64/qt5/plugins/org.kde.kdecoration2/kwin5_aurorae.so
#6 0x00007f63e25532be in () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#7 0x00007f63e255214e in () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#8 0x00007f63e255172d in () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#9 0x00007f63e254688e in () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#10 0x00007f63e253bdba in GtkConfig::setWindowDecorationsAppearance() const () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#11 0x00007f63e253eb21 in GtkConfig::applyAllSettings() const () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#12 0x00007f63e253f039 in GtkConfig::GtkConfig(QObject*, QList<QVariant> const&) () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#13 0x00007f63e2540679 in QObject* KPluginFactory::createInstance<GtkConfig, QObject>(QWidget*, QObject*, QList<QVariant> const&) () at /usr/lib64/qt5/plugins/kf5/kded/gtkconfig.so
#14 0x00007f640e8a1157 in KPluginFactory::create(char const*, QWidget*, QObject*, QList<QVariant> const&, QString const&) () at /usr/lib64/libKF5CoreAddons.so.5
#15 0x000055c9729743c2 in ()
#16 0x000055c97297543f in ()
#17 0x000055c9729758bf in ()
#18 0x000055c97296fad2 in ()
#19 0x00007f640d8d534d in __libc_start_main () at /lib64/libc.so.6
#20 0x000055c97296fd0a in ()
[Inferior 1 (process 10464) detached]
Is this something that is happening generally or specific to my system?
A little more information. Based on the backtrace, it appears the problem has to do with gtkconfig.so. This is supplied in the package kde-gtk-config5. The update installed version 5.22.90 from the kde framework repository from which I get all framework packages as I’ve given the repository a high (75) priority per instructions from an Opensuse wiki to assure that my Framework packages came from this repository. I did the same for QT5. Many other packages are at the 5.22 level from the Framework repository and have been installed. Version 5.18.5 of the kde-gtk-config5 package is available from the regular main repository or backport update repository. As an experiment, I installed this version and the problem went away. So, it seems there is a bug in the 5.22.90 version of this file. Of course now, since I loaded a version from a different repository, I could get dependency problems in the future. So this seems like a very unsatisfactory solution.
Just to wrap this up. After some exploration, it seemed to me like the problem was in window decorations. Apparently kded was looking for a theme called aurorae and crashing because of a missing call in that routine. I had never heard of aurorae and wondered if changing the decorations in KDE settings would have any effect. When I looked in the KDE settings GUI I was offered two icon themes - Breeze and Plastik - no aurorae and neither was checked. I highlighted Breeze and hit apply and the error messages stopped, Kmail reappeared in the system tray (a major symptom was that applications I had appearing in the system tray had disappeared), and all was right with the world.