Hi.
Every time installing system I getting a headache with tons of bugs that built in a new KDE versions.

This time I got a problem with tray (or how does it named) icons.
I installed kmix (sound mixer) and added keyboard layout and proceeded with other tweaks/settings. And suddenly I realized that mixer icon and keyboard layouts indicator disappeared. Though kmix process is running, and keyboard layout works (I can switch layouts and see how keyboard led indicates it).

Tried to reinstall kmix with no luck. Added another one instance of System Tray applet to panel -the same...

Anyone experienced such a problem?

In the System Tray settings, there's a setting to always show all icons. I don't use it, but I've never had problems with icons disappearing. I usually specify one by one which icons to always show or hide.

I'm aware of that settings, but unfortunately settings dialog inaccessible. I do not know how to launch it when icons are invisible

Found it: System Settings-> Startup And Shutdown-> Background Services-> Status Notifier Manager