Of all the great new things that arrived in KDE 4.8 one of the most annoying to me was the inclusion of a browser and file manager launcher in the Task Manager. These are the little icons that appear when the said application is not running.
I tried to remove the launchers with the usual right mouse menu option but everytime I re-booted I ended up with the icons back again.
I have finally figured it out though. For some reason you need to remove the Task Manager from the panel and add a new instance of Task Manager and that seems to solve the problem.
While it is a 2 minute fix it is something that should just work by default I think.