I have the same problem as above post.

This is my module config:

{
		  module: 'MMM-CalendarExt2',
		position: 'top_left',
		  config: {
		    calendars : [
			{
			    name: "US holiday",
			    icon: "noto-beach-with-umbrella",
			    className: "holiday",
			    url: "http://www.calendarlabs.com/templates/ical/US-Holidays.ics",
			  },
		    ],
		    views: [
		      {
			mode: "month",
			calendars: [],
		      },
		    ],
		    scenes: [
		      {
			views: [],
		      },
		    ],
		  },
		},

WIth this code I get the same picture as above.

I have no problem with the standard calendar.