Resolving KDE6 Panel Freeze

Whenever the plasma shell crashes, that is the panels (wherever you have them) are no longer responsive you can do the following to resolve the issue.

From a terminal run the following command:

killall -TERM plasmashell

Wait for the application panels to disappear. If it doesn't then replace -term with -9 and as soon as the panels disappear run the following:

kstart plasmashell

If all goes well you should now have working panels. You can also close the terminal window/tab, as you will get diagnostic information, echoing to the terminal window, that you ran the command from.