bug#41544: 26.3; Possible incorrect results from color-distance

[Eli Zaretskii]

> From: Mattias Engdegård <mattiase@acm.org>
> Date: Sun, 31 May 2020 22:46:07 +0200
> Cc: Simon Pugnet <simon@polaris64.net>, 41544@debbugs.gnu.org,
>         Eli Zaretskii <eliz@gnu.org>
> 
> Proposed patch attached. I found css-mode no worse than before (a tad better, 
> if anything). Perhaps we need to decompress to linear components after all, 
> but at least now there is a single place to do it.
> 
> (Should list-colors-display use color-dark-p for the text in its left column, 
> by the way? Or is there a point in not doing so?)

Please remind me why do we want to make such deep and wide changes in
our color system?  Is that just because we have a minor bug in
color-distance?  Wouldn't it be better to just fix that one bug?

I'm worried because the way our automatic color mapping on
color-challenged TTYs works took some time to get right, and it worked
well for years.  If we want to risk rocking that particular boat som
profoundly, we had better had a very good reason, preferably several
good reasons.

Thanks.