I have the same issue after updating today. This is what appears in system log:
Oct 07 23:38:00 localhost.localdomain plasmashell[3571]: dbus[3571]: arguments to
dbus_message_new_method_call() were incorrect, assertion "destination == NULL ||
_dbus_check_is_valid_bus_name (destination)" failed in file ../../dbus/dbus-message.c
lin>
Oct 07 23:38:00 localhost.localdomain plasmashell[3571]: This is normally a bug in some
application using the D-Bus library.
Oct 07 23:38:00 localhost.localdomain plasmashell[3571]: D-Bus not built with -rdynamic
so unable to print a backtrace
Oct 07 23:38:00 localhost.localdomain plasmashell[3571]: KCrash: Application
'plasmashell' crashing...
Oct 07 23:38:00 localhost.localdomain plasmashell[3571]: KCrash: Attempting to start
/usr/libexec/drkonqi
Oct 07 23:38:01 localhost.localdomain systemd[1766]: plasma-plasmashell.service: Main
process exited, code=exited, status=253/n/a
Oct 07 23:38:01 localhost.localdomain systemd[1766]: plasma-plasmashell.service: Failed
with result 'exit-code'.
Oct 07 23:38:01 localhost.localdomain systemd[1766]: plasma-plasmashell.service: Consumed
3.136s CPU time.
Oct 07 23:38:01 localhost.localdomain systemd[1766]: plasma-plasmashell.service: Scheduled
restart job, restart counter is at 5.
Oct 07 23:38:01 localhost.localdomain systemd[1766]: Stopped plasma-plasmashell.service -
KDE Plasma Workspace.
Oct 07 23:38:01 localhost.localdomain systemd[1766]: plasma-plasmashell.service: Consumed
3.136s CPU time.
Oct 07 23:38:01 localhost.localdomain systemd[1766]: Starting plasma-plasmashell.service -
KDE Plasma Workspace...
Oct 07 23:38:02 localhost.localdomain systemd[1766]: Started plasma-plasmashell.service -
KDE Plasma Workspace.