Set cell background instead of holiday event - MMRIZE/MMM-CalendarExt3 GitHub Wiki

eventTransformer: (ev) => {
  if (ev.calendarName === 'US Holiday') ev.skip = true
  return ev
},
manipulateDateCell: (cellDom, events) => {
  if (Array.isArray(events) && events.some(e => e.calendarName === 'US Holiday')) {
    cellDom.style.backgroundColor = "rgb(255 0 0 / 20%)"
  }
},