Dropdown Menu Control separator (- bug

I am building a mogrt. I use a dropdown menu to choose between 20 preset color combinations. To make the ux a bit more comprehesive I want to use separator-lines between diffrent groups. The way to do that is to name items "(-". The problem is I can only make 1 separator line. If I try to edit more than on item the change just gets ignored. When I edit, write "(-", press enter it goes back to be named "Item 5".

Is this a bug or can you realy only use one separator line?

I am using AE 23.2

Mac OS 13.2 (22D49)

MacBook Pro M1 Max