Re: Adequacy of min-colors thresholds

On Mon, 13 Jul 2026 19:42:52 +0000 Heime <[email protected]> wrot=
e:

> On Tuesday, July 14th, 2026 at 6:25 AM, Eli Zaretskii <[email protected]> wro=
te:
>
>> > Date: Mon, 13 Jul 2026 17:44:17 +0000
>> > From: Heime <[email protected]>
[...] =20
>> > And what is a (min-colors 88) exactly?
>>=20
>> Any terminal that supports at least 88 colors.
>
> Why the chosen 88?  Is that some special terminal support?=20

See https://www.invisible-island.net/xterm/xterm.faq.html#color_by_number:

  In development of xterm over the past 20 years, we
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  * incorporated ANSI (8) colors,
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  * adapted the aixterm feature (16) colors,
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  * added extensions for 88- and 256-colors.
  [...]
  The 256-color extension came first. 88-colors (using the same control
  sequence) came next, to reduce the amount of memory needed. XTerm
  stores both foreground and background color indexes for each cell on
  the screen. That is two bytes, which doubled the amount of memory used
  by xterm for the scrollback. More important, however, was the number
  of entries in the colormap. With 256 colors, 65536 entries might be
  used, but 88 colors use at most 7744 entries. In the late 1990s,
  inexpensive displays were far less capable, requiring workarounds to
  get acceptable performance.

Steve Berman