That new accordion styled layoutblocks and the buttons

For my most wanted feature, the accordion, which we now can use with a state button and a corresponding layoutblock, I only dream of kind of different states: we can use “normal”, “rollover/mouseover” and “Active” while the active state in the case of acccordions only shows the “click” state and not the real active state, which is, when the accordion, the layoutblock is showing up. An example, I once did is here: Sachverständiger für Natursteinarbeiten

SO as far as I experienced, One cannot put different symbols in a state button for its different states like here the “+” and “x”.

Thanks in advance and Kind Regards,
Uwe