bug#39649: 27.0.60; tab-line doesn't scroll

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Date: Tue, 25 Feb 2020 23:20:10 +0200
> Cc: 39649@debbugs.gnu.org
> 
> I see that left/right arrows in your bug report are XPM images.
> But I don't understand how this is possible because
> (info "(efaq-w32) Image support") says that Emacs has
> no built-in support for XPM on Windows.

That's not what the w32 FAQ says.  It says this:

  Emacs has built in support for XBM and PBM/PGM/PPM images.  This is
  sufficient to see the monochrome splash screen and tool-bar icons.
  Since v22.2, the official precompiled binaries for Windows have bundled
  libXpm, which is required to display the color versions of those images.

IOW, XPM support is not built-in, but MS-Windows binaries of all Emacs
versions since v22.2 are distributed with the libXpm library, which
allows the w32 build to display XPM images.