Additional Fields And Rows In FullCalendar V4

I'm using the latest V4 version of FullCalendar and I can't seem to be able to add additional fields like description and notes in my case. I use the daygrid view and I would like

Solution 1:

eventRender: function(info) { 
  info.el.querySelector('.fc-desc').innerHTML = "" + info.event.description + "";
}

This solved my problem, thanks to ADyson for help.