Comment # 19 on bug 913339 from Wolfgang Bauer

I think we can close this now.
Old-style system tray icons are again displayed properly meanwhile, and this is
what this bug report originally was about.

If you still have problems with one particular icon, please report it
separately.

As mentioned already there's still an upstream problem that causes system tray
plasmoids (e.g. the volume control or plasma-nm) missing sometimes, though:
https://bugzilla.opensuse.org/show_bug.cgi?id=955895
https://bugs.kde.org/show_bug.cgi?id=352055