bug#71745: 29.3; Customize face re-selects unselected items, leading to broken

[Eli Zaretskii <eliz@gnu.org>]

> From: Sam Hedin <sam.hedin@gmail.com>
> Date: Mon, 24 Jun 2024 08:51:57 +0200
> 
> Once opening the customize buffer all checkboxes are selected by
> default, even if they were de-selected by the user previously, which
> means that the user may unintentionally change settings they didn't
> intend to.
> 
> Emacs -Q -> M-x customize-face -> default -> deselect
> Foreground/Background -> click Apply. Close the buffer, then open the
> customization again. Note that the foreground/background checkboxes are selected again.

Do you see this only for the default face or for other faces as well?

I can only reproduce this for the default face.  Which looks correct
to me, because it is meaningless to uncheck any attributes of the
default face: the default face must always have all the attributes
specified explicitly.

> The result of this is that using the customize buffer may have
> unintended side effects. In my case, I opened the
> customize buffer only to change the font, but accidentally defined a
> foreground and background color in the process which led to some themes breaking. This is most noticeable
> when opening the customize buffer when using a light theme, saving, then loading a dark theme. For example
> modus-operandi/modus-vivendi.

Please show an example with some other face, and let's take it from
there.

Thanks.