In QML plasmoids the configuration is completely handled by KConfig XT. This works great, except that I miss the ability to add something like this: <entry name="icon" type="Icon"> <label>Icon on the launcher button</label> <default>start-here-kde</default> </entry> This entry should happily cooperate with the KIconButton which I put in contents/ui/config.ui An example where this is useful is to allow users to change the icon on the launcher button of a menu plasmoid (such as Kickoff or Lancelot or the appmenu-qml plasmoid on http://kde-apps.org).
This bug applies to a version of Plasma which I am no longer using. Closing.