The thing that kills me is that Nextcloud had an _amazing_ calendar a few years ago. It was way better than anything else I have used. (And I tried a lot, even the calendar add-on for Thunderbird. Which may or may not be built in these days, I can't keep track.)

Then at some point the Nextcloud calendar was "redesigned" and now it's completely terrible. Aesthetically, it looks like it was designed for toddlers. Functionally, adding and editing events is flat out painful. Trying to specify a time range for an event is weird and frustrating. It's better than not having a calendar, but only just.

There are plenty of open source calendar _servers_, but no good open source web-based calendars that I have been able to find.