Right-click on Kicker -> Add New Panel -> KSim. (No, I wouldn't have thought of looking there either--I didn't even know I had it installed until I asked my package mangler about it.)
Ah! Mystery solved. :)
Makes sense now that I know. I have long, long not paid attention to that menu option.
Long story is I'm updating help handbooks. I wanted to discover whether the KSim handbook is accessible through the app. The handbook is a useless template shell anyway, but I wanted to confirm the handbook is accessible somehow, somewhere. Test: no, the popup Help option does nothing, the preferences dialog Help button opens the kicker handbook rather than the ksim handbook. This latter result seems to affect all applets too.
These panel extensions do not appear anywhere in the help handbook table of contents (TOC). There is a TOC entry for Konqueror Plugins. Perhaps there should be one for Panel Extensions?
Darrell