[xwiki-devs] Crafting method to add a plugin to the CKEditor?

Hello fellow developers, is there some hint to add a plugin (with a button) to the CKEditor? I've met /xwiki/bin/edit/CKEditor/EditSheet?editor=object which is probably the place to start with. I tried adding the extraConfigs variable within the configuration but it seems like this cannot load my plugin. It would be cool to have an extension mechanism for that. thanks in advance. Paul