Re: master d423017cae1: * lisp/vc/vc-dir.el (vc-dir-headers): Try a hints separator line.

> Date: Fri, 28 Aug 2026 06:13:48 +0300
> From: Dmitry Gutov <[email protected]>
> 
> On 21/08/2026 16:39, Sean Whitton wrote:
> > Dmitry Gutov [18/Aug  4:56pm +03] wrote:
> >> On 18/08/2026 12:53, Sean Whitton wrote:
> >>> Dmitry Gutov [16/Aug  2:38am +03] wrote:
> >>>> But how about this one? strike-through goes right through the middle.
> >>>> Not sure why Lars chose underline originally - this seems to work fine
> >>>> on all the terminal emulators I've tested, and where it doesn't (tty),
> >>>> neither does underline.
> >>>
> >>> This looks great in my terminal but I feel the graphical display is a
> >>> bit too cramped -- could we tweak it further?
> >> I think the appropriate amount of spacing depends on the user's habit,
> >> and the GUI often has smaller margins.
> >>
> >> So this element looks cramped on GUI after spending time in the terminal
> >> and the terminal looks too spacey still after using the GUI version.
> >>
> >> I think that's ultimately fine because on the GUI at least the user can
> >> choose between the shapes by customizing the face 'separator-line'.
> > 
> > SGTM.  Please install.
> 
> Thanks, I've pushed 22bf7a9821e.

I apologize for not catching this discussion in time, but IMO this
change is more backward-incompatible than it should be.  It's okay to
add strike-through on terminals which support that, but why break
those which don't and only have underline?  The argument that
strike-through "seems about as common as underline" is the proverbial
famous last words; we don't really need to have even a slightest risk
here, because "we have the technology" to support both cases.

So please let's fix the defface so that it uses strike-through when
supported, otherwise uses underline, and let's augment the change in
make-separator-line so that it also supports terminals without support
for strike-through but which support underline.  Okay?