Zarlin

Maybe mermaid fits your use case?

https://mermaid.js.org/

I use OneCalendar, it works with a lot of email/calendar hosts, looks good, and is very responsive.

Alternatively, Thunderbird has a calendar feature built-in.

(Edit) failed to see which community this was, OneCalendar is sadly not open source.

Reminds me of this gem: https://lizengland.com/blog/2014/04/the-door-problem/

winget install Mozilla.Firefox

No need to even open Edge or Chrome

This can actually be caused by using mixed line endings. Which is a whole new class of horrible.

I think you mean this one?

https://xkcd.com/927/