Modus themes 2.7.0 for GNU Emacs

I just published the latest stable release of the Modus themes. The change log entry is reproduced below. For any questions, feel welcome to contact me.

I will now prepare the patch for emacs.git (currently Emacs 29) which will then trickle down to GNU ELPA (the modus-themes is a :core package). Thank you for your patience!

Package name (GNU ELPA): modus-themes (also built into Emacs >= 28)
Official manual: https://protesilaos.com/emacs/modus-themes
Change log: https://protesilaos.com/emacs/modus-themes-changelog
Colour palette: https://protesilaos.com/emacs/modus-themes-colors
Sample pictures: https://protesilaos.com/emacs/modus-themes-pictures
Git repo on SourceHut: https://git.sr.ht/~protesilaos/modus-themes
- Mirrors:
  - GitHub: https://github.com/protesilaos/modus-themes
  - GitLab: https://gitlab.com/protesilaos/modus-themes
Mailing list: https://lists.sr.ht/~protesilaos/modus-themes
Backronym: My Old Display Unexpectedly Sharpened … themes

Support for packages or faces

Reinstated support for centaur-tabs. I had removed it in commit 2235ce5 (done on 2022-08-02) for version 2.5.0 of the modus-themes. At the time I wrote:

centaur-tabs has a bug where it cannot read the value of a face if it
uses the standard `:inherit` attribute.  I have sent a patch to fix it,
but have received no response since February:
<https://github.com/ema2159/centaur-tabs/pull/179>.

Relevant reports:

- <https://github.com/protesilaos/modus-themes/issues/30>
- <https://gitlab.com/protesilaos/modus-themes/-/issues/288>
- <https://github.com/protesilaos/modus-themes/issues/15>

I am happy to reinstate support for centaur-tabs as soon as the package
gets the maintenance it needs.

My patch/pull-request is now merged and the package is actively maintained once again. Hence the decision to bring back support for it, as promised.

Applied styles for the icon-button face of Emacs 29.
Styled the log-edit-headers-separator face of Emacs 29 (it was introduced upstream by a patch of mine).
Made the gnus-summary-low-unread face inherit from the italic face like the rest of that subgroup of faces. This helps differentiate it from the gnus-summary-high-unread face. Thanks to Mark Simpson for pointing out the possibility of conflating those two faces: https://lists.sr.ht/~protesilaos/modus-themes/%3Cm2r0zszc2z.fsf@gmail.com%3E.
Covered the read-multiple-choice-face by adding a noticeable background colour to it. The default attributes it has, which look like other key bindings (bold and blue) plus an underline are technically okay, though the context of this face is in the echo area which is one line tall. Moreover, the highlighted keys are inlined with other text. These make it difficult to spot the highlights without some extra spacing. I use the addition of a background in Org’s export dispatcher interface which also has some unique requirements (the org-dispatcher-highlight face). The principle is to have theme-wide consistency (e.g. “all key bindings must look the same”) EXCEPT when the specifics require a different set of styles in the interest of usability.
Extended the coverage of the auctex package’s faces to include the font-latex-underline-face. Thanks to Luis Miguel Castañeda for reporting a typo I made which caused an error: https://lists.sr.ht/~protesilaos/modus-themes/%3C7h7d2oudpb.fsf@imaginarymagnitude.net%3E
Added support for crontab-mode. Thanks to Antonio Ruiz for the patch: https://lists.sr.ht/~protesilaos/modus-themes/patches/35080. It is below the ~15 line threshold and thus requires no copyright assignment to the Free Software Foundation.
Extended support for the company package’s company-scrollbar-bg and company-scrollbar-fg faces.
Added support for the spell-fu package. Thanks to Antonio Ruiz for the patch: https://lists.sr.ht/~protesilaos/modus-themes/%3C87fshnq7uv.fsf%40purelymail.com%3E. Same as further above for Antonio’s copyright status.
Moved the selectrum-prescient faces to the prescient group, to be consistent with changes in the respective upstream packages. Thanks to okamsn for the contribution, which was done in pull request 41 on the GitHub mirror: https://github.com/protesilaos/modus-themes/pull/41. The user okamsn has assigned copyright assignment to the Free Software Foundation, although this patch is within the allowed limits.

Change to ‘fill-column-indicator’

Made the fill-column-indicator face more noticeable. It is what the display-fill-column-indicator-mode uses to draw a line on where the fill-column is.

This change is in response to private messages I received as well as this, at parts impolite and toxic, thread that I refrained from participating in: https://lists.gnu.org/archive/html/help-gnu-emacs/2022-08/msg00255.html.

[ I do not follow that mailing list, by the way. All my projects have multiple communication channels and I always reply in a timely fashion. Social media, fora about Emacs, generic mailing lists, etc. are not among those channels. https://protesilaos.com/codelog/2022-07-24-report-issues-official-channels/. ]

The core idea is that the previous design was (1) considered “invisible” and (2) it prevented the customisation of the user option display-fill-column-indicator-character.

I am addressing point 1, but point 2 puts us in an awkward spot as we would then not be allowed to use a background and a height value. Not doing so produces a dashed line by default, with the dashes further apart the greater the line-spacing is (especially in, say, Org headings that can have a greater height than paragraph text). It looks broken and I keep getting requests to fix what is not the themes’ fault. So no, the themes will remain opinionated in this regard by ignoring display-fill-column-indicator-character through the styling they apply to make the line contiguous.

For context, also read Emacs bug#57424 and please don’t take my words in a private message out of context. If I need to state my opinion in a public setting, I know how to do it. https://debbugs.gnu.org/cgi/bugreport.cgi?bug=57424.

Refinement to modus-vivendi ‘bg-diff-focus-removed’ colour

Made the default removed diff background slightly more luminant. The colour is seen in diff-mode, ediff, and the Magit focused diff hunk.

When the user option modus-themes-diffs is set to either bg-only or desaturated, this colour is used to highlight word-wise (“refined”) changes. The increased luminance lets it stand out more compared to the more subtle backdrop.

Thanks to Kévin Le Gouguec for bringing this issue to my attention and for discussing it with me: https://lists.sr.ht/~protesilaos/modus-themes/%3C87bks4i9tg.fsf@gmail.com%3E

Note about ‘goto-address-mode’

Quote from the manual:

The built-in 'goto-address-mode' uses heuristics to identify URLs and
email addresses in the current buffer.  It then applies a face to them
to change their style.  Some packages, such as 'notmuch', use this
minor-mode automatically.

The faces are not declared with 'defface', meaning that it is better
that the theme does not modify them.  The user is thus encouraged to
consider including (or equivalent) this in their setup:

    (setq goto-address-url-face 'link
          goto-address-url-mouse-face 'highlight
          goto-address-mail-face 'link
          goto-address-mail-mouse-face 'highlight)

My personal preference is to set 'goto-address-mail-face' to nil, as
it otherwise adds too much visual noise to the buffer (email addresses
stand out more, due to the use of the uncommon '@' character but also
because they are often enclosed in angled brackets).

Changes to the manual

Fixed a few typos and ensured that spelling using American English as that is what emacs.git requires.
Added the missing :config keywords from the example configuration of the circadian package. Thanks to Koen van Greevenbroek for the patch: https://lists.sr.ht/~protesilaos/modus-themes/%3C8735cb6zm3.fsf%40posteo.net%3E.