bug#62370: 28.1; sieve-mode: faces should inherit from font-lock-X-face faces

[Gregory Heytings]

> > I think sieve-mode should inherit from font-lock-*-face, as most other 
> > things do.
>
> I'm not sure I agree.  These faces are with us for a long time, so 
> changing their defaults now brings disadvantages: it could cause someone 
> dislike the result.
>
> Does anyone else have an opinion about this?

I agree with both Trent and you.

Modes should inherit from font-lock-*-faces, unless there's a good reason 
not to inherit from these faces.  Otherwise customizing the visual 
appearance of Emacs is a nightmare.  This is, by the way, made clear in 
(elisp)Major Mode Conventions: "Each face that the mode defines should, if 
possible, inherit from an existing Emacs face.  See Basic Faces, and see 
Faces for Font Lock."

But the sieve-* faces have existed for twenty years, so it's now too late 
to change them.