bug#57499: Documentation bug in the docstring of set-face-attribute?

[Eli Zaretskii <eliz@gnu.org>]

> Date: Wed, 31 Aug 2022 12:04:03 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: 57499@debbugs.gnu.org
> 
> > This was discussed in bug#54156.  Are there any new findings or 
> > considerations that would require to reopen that discussion?
> >
> 
> As far as I can tell, there are, but if you disagree, feel free to close 
> the bug.  Bug#54156 starts with someone telling that
> 
> (set-face-attribute 'some-face nil :background nil)
> 
> did not have an effect in new frames.  To which you replied:
> 
> >
> > The correct way to do [that] is this:
> > 
> > (set-face-attribute 'some-face nil :background 'unspecified)
> > (set-face-attribute 'some-face t :background 'unspecified)
> >
> > That is, one must explicitly call set-face-attribute with FRAME = t (as 
> > well as nil), and pass 'unspecified' (NOT nil!) as the value.
> >
> 
> and you later added that the call with frame = t is "a special trick to 
> override defface with 'unspecified'".
> 
> It seems however that the call with frame = t is unnecessary, or at least, 
> I could not come up with a scenario in which the first call does not also 
> affect new frames.

I still don't understand what is new here.  All of that was said in
that old discussion. no?

Or let me turn the table and ask: what do you want to change in the
current doc string?  You want to tell that nil requires 2 calls, but
unspecified doesn't?