ICS content type not found

I cannot get working a custom ICS content type.

In my calendar.ics.twig file, I fetch my events and output them as iCal (also tried calendar.ical.twig). Adding a calendar.md in user/pages/calendar, I create the entry point. Howerever, when I access the url /calendar.ics, GRAV returns 404 Page not found.

As notice: other content types such as json and html are working for the same page type (calendar.json.twig and calendar.html.twig).

I add the custom content type in a theme. Therefore I added following blueprints to theme://blueprints:

config/media.yaml

types:
  ics:
    type: iCal
    thumb: media/thumb-ics.png
    mime: text/calendar

config/system.yaml

pages:
  types: [html,htm,xml,txt,json,rss,atom,ics]

I checked these pages for help, but still not get it working.

• Docs
• Forum

Did I miss something or is that still a bug of GRAV?