bug#51590: follow-mode is broken with header-line and tab-line

[Alan Mackenzie <acm@muc.de>]

Hello, Eli.

On Sun, Nov 07, 2021 at 15:14:13 +0200, Eli Zaretskii wrote:
> > Date: Sun, 7 Nov 2021 12:48:22 +0000
> > Cc: Eli Zaretskii <eliz@gnu.org>, 51590@debbugs.gnu.org
> > From: Alan Mackenzie <acm@muc.de>

> > > Indeed, I tested with the header-line, and it has the same problem,
> > > so retitled this bug report.

> > > After trial and error, I arrived to the following patch that completely
> > > fixes these problems.  However, I can't explain how it works.

> > I've spent some time on this patch, and I've transformed it into a
> > similar patch that I can explain, and I believe is nearly correct[*].
> > Could you possibly try it out in your system.  Thanks!

> So what's the verdict about posn-at-x-y? does it have a bug when
> tab-line is present, or doesn't it?

There is no bug there.  It was merely me getting confused between tab
lines and tab bars.  The first of these is part of the window, the
second part of the frame.

I closed bug #51632 as notabug late last night.  Sorry I neglected to
put you onto the Cc:.

I think there are still inconsistencies in the documentation with the
terms "window body" and "window text area", but I'll have to look at
that more systematically to find them, if they are there.

-- 
Alan Mackenzie (Nuremberg, Germany).