bug#73862: [PATCH] Add `header-line-active` and `header-line-inactive` faces.

[Eli Zaretskii <eliz@gnu.org>]

> From: Eshel Yaron <me@eshelyaron.com>
> Cc: Aaron Jensen <aaronjensen@gmail.com>,  monnier@iro.umontreal.ca,
>   trevor.m.murphy@gmail.com,  73862@debbugs.gnu.org
> Date: Sun, 08 Dec 2024 15:11:07 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > We also haven't yet heard from Eshel.
> 
> I don't have any concrete suggestions at this point.  It's surely a
> complicated situation.

Did you try the patch I posted, and if you did, did it resolve your
original problems?  That's what I wanted to hear, since you were one
of the two persons who raised these issues.

> The workaround of remapping both header-line-active and
> header-line-inactive instead of header-line seems to work.  The way I
> see it, the essence of the issue is that the "face" abstraction is
> leaky, in the sense that some faces (these "basic faces") behave
> differently from other faces in some cases that involve inheritance and
> remapping.

AFAIK, only face-remapping behaves differently, and only when a basic
face inherits from another.  The inheritance itself work as with other
faces.

> I think this calls for either changing the way basic faces are
> handled so they do behave like any other face, or clearly
> documenting their subtleties.

Patches to rework the faces support so that these idiosyncrasies are
removed will be most welcome.  I just don't plan on doing that myself,
as I won't have time for that.

TIA