I'm trying to add a section in the wordpress customizer with a few different "subsections" in a dropdown menu. Like in the following image:
I would like to open a subsection when you make click on "H1", for example, with some new controls. I know how to use add_panel, add_section, add_control but not how to manipulate the html code of each section. It's possible because i saw it in several themes and plugins but i can't find any way to do it. I was thinkig to add some html blocks and hide/show by jquery with the customize_controls_print_footer_scripts but javascript functions doesn't seems to work properly. It's frustrating because i cant find any information about that on internet