bug#64725: 30.0.50; set-face-foreground shows background colors

[Helmut Eller]

On Wed, Jul 19 2023, Eli Zaretskii wrote:

>> It would be more useful to see the text with the candidate color as
>> foreground on the default background.
>
> Why not use the actual foreground of the face being customized?  Then
> the user could see whether the background color being selected will
> have good contrast (or just look well) with the face's foreground.

I don't understand what you mean with "actual foreground". 

The problem I have, is that some color combinations are hard to read,
like yellow on white.  Then I usually want to change the foreground
color and not the background.

Assume that we have white as default background, black as default
foreground, font-lock-string-face has foreground yellow and we want to
change the foreground from yellow to brown.

In this situation I would like to see how brown on white would look and
not so much black on brown (or white on brown).

Even better then displaying the candidate color on the default
background would be to show the candidate color on the current
background color of the face.  But I guess that's harder to implement.

Helmut