schedule.ics doesn't work on calendar.google.com
The https://static.gnome.org/calendars/schedule-unstable.ics calendar doesn't work on https://calendar.google.com. Unfortunately, no errors are printed, just an empty calendar is shown. If I download the .ics
file, it obviously contains some events. The schedule used to work there years ago, but it doesn't work some time already, any idea why?