CKEditor config

I’m trying to change CKEditor config in Omeka S 4.0.4 to activate more plugins both for page and for item/media editing, but I’m not able to find the right place.
ckeditor-config.js in /application/asset/js seems to be ignored …
Can anyone help me?

That should be the right place, well ckeditor_config.js that is. What are you trying to change?

I’m trying to change the active plugins and the structure of the menu, but it doesn’t work.