bug#23571: 25.1.50; Click-mouse-1 = Drag-mouse-1 in Gnus Article buffer

[Eli Zaretskii]

> From: Stephen Berman <stephen.berman@gmx.net>
> Date: Thu, 26 May 2016 18:09:56 +0200
> 
> On Wed, 18 May 2016 15:27:23 +0200 Stephen Berman <stephen.berman@gmx.net> 
> wrote:
> 
> > Clicking mouse-1 in a Gnus Article buffer, then releasing it and moving
> > the mouse (without holding down a mouse key) highlights a region, just
> > as when the mouse is dragged with mouse-1 held down.  To reproduce:
> >
> > 0. emacs -Q
> > 1. M-x gnus, type `y' at the prompt, then type `B RET news.gmane.org RET
> >    1 RET' to open the most recent article in gmane.announce on the
> >    news.gmane.org server.
> > 2. Click anywhere in the Article buffer (except on the texts following
> >    the From: and To: headers, which are buttons) with mouse-1, release
> >    mouse-1, move the mouse.
> > => A region is highlighted.
> >
> > Subsequently clicking and releasing mouse-1 does not deactivate the
> > mark (but clicking with mouse-2 or mouse-3 does).
> >
> > I have not observed this behavior anywhere besides Gnus Article buffers.
> >
> > This happens in master but not in emacs-25.  It happens at least since
> > commit 62d7acae7405732268713006d839a5c3507b9482, which was my first
> > build from master after a long pause, so I don't know when this behavior
> > first appeared (I didn't save any earlier builds from master, which were
> > from many months before, but I'm sure they didn't show this behavior).
> 
> Git bisect says:
> 
> 72166f2f3dba18f1217c666574032f5a0351ed65 is the first bad commit
> commit 72166f2f3dba18f1217c666574032f5a0351ed65
> Author: Martin Rudalics <rudalics@gmx.at>
> Date:   Tue May 3 08:38:49 2016 +0200
> 
>     Bind `widget-button-click' to mouse-1/-2 instead of down-mouse-1/-2
>     
>     * lisp/wid-edit.el (widget-keymap): Bind `widget-button-click'
>     to mouse-1/-2 instead of down-mouse-1/-2.  Suggested by Stefan
>     Monnier.  (Bug#19185, Bug#20398)

So I guess Gnus needs to do something to countermand the low-level
change, right?