Guys,got a problem. System tray with clock just moved to left,where quick start panel is and I cant see opened windows. I know thats stupid but very uncomfortable. Help me pls 
P.S. KDE
This happened to me last week, I never solved it, just rebuilt the panel and task bar… V. annoying. Is there an “invisible” panel now at the top of your screen?
Hi,
Not sure I fully understand your problem but my guess is that your Task Manger somehow got deleted. Make sure widgets are unlocked and then right click on your panel and choose Add Widget. Find the Task Manager widget and drag it to the panel.
Take Care,
Ian