Bug#874529: And here is an unoffical updated package that fixes it.

[hendriksen.a.a at gmail.com]

Using the fix from github, I have created new packages. 

I have attached the updated packages. 

I have spent a good two hours trying to find out how to do a proper
'pull request' or something similar for Debian. 

I this works out :) 

On Thu, 21 Sep 2017 09:59:06 +1200 Eliot Blennerhassett <ewblen at gmail.c
om> wrote:
> https://github.com/GNOME/gdm/commit/60447f2016cd873b0a62a5885687d7b3a
8538d11#diff-daf9735fd40f92ad94e330eeab3c99a7
> 
> 
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Format: 1.8
Date: Fri, 05 Jan 2018 22:27:34 +0100
Source: gdm3
Binary: gdm3 libgdm1 libgdm-dev gir1.2-gdm-1.0
Architecture: source amd64
Version: 3.22.3-4+deb9u1
Distribution: UNRELEASED
Urgency: medium
Maintainer: Debian GNOME Maintainers <pkg-gnome-maintainers at lists.alioth.debian.org>
Changed-By: Allard Hendriksen <hendriksen.a.a at gmail.com>
Description:
 gdm3       - GNOME Display Manager
 gir1.2-gdm-1.0 - GObject introspection data for the GNOME Display Manager
 libgdm-dev - GNOME Display Manager (development files)
 libgdm1    - GNOME Display Manager (shared library)
Changes:
 gdm3 (3.22.3-4+deb9u1) UNRELEASED; urgency=medium
 .
   * Backports user switching patch.
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