bug#60987: 30.0.50; Calendar not accepting custom holidays

[Eli Zaretskii]

> Date: Sun, 22 Jan 2023 18:04:27 +0100
> From: "Emanuele M. Monterosso" <emanuele.monterosso@gmail.com>
> 
> >Maybe it's a problem with the Emacs 30 build you used?  It isn't a
> >build from the Emacs repository, so perhaps it has some changes that
> >cause this?
> 
> It could be, but it also did happen in WSL (tho I can’t use emacs from there 
> due to work policies) emacs
> build
> 
> From the Ubuntu Emacs Lisp ppa 
> https://launchpad.net/~ubuntu-elisp/+archive/ubuntu/ppa.

Can someone else please reproduce this and investigate?