Most Guix system setup with desktop evironment will install GDK_PIXBUF_MODULE_FILE
environment variable in the system profile, and it'll be leaked into the sandbox
environment of flatpak, so the applications in sandbox may fail to find correct
GdkPixbuf loaders.

This patch unset the GDK_PIXBUF_MODULE_FILE environment variable before running
the sandboxed applications, prevents it to load GdkPixbuf loaders from the path
of host system.

--- a/common/flatpak-run.c
+++ b/common/flatpak-run.c
@@ -1853,6 +1853,7 @@ static const ExportData default_exports[] = {
   {"GST_PTP_HELPER", NULL},
   {"GST_PTP_HELPER_1_0", NULL},
   {"GST_INSTALL_PLUGINS_HELPER", NULL},
+  {"GDK_PIXBUF_MODULE_FILE", NULL},
 };
 
 static const ExportData no_ld_so_cache_exports[] = {
ion value='koszko-scripts'>koszko-scripts</option>
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<div class='path'>path: <a href='/guix/log/?id=bcea3c11d691712039addc4037943b257e9d7967'>root</a>/<a href='/guix/log/gnu?id=bcea3c11d691712039addc4037943b257e9d7967'>gnu</a>/<a href='/guix/log/gnu/services?id=bcea3c11d691712039addc4037943b257e9d7967'>services</a>/<a href='/guix/log/gnu/services/spice.scm?id=bcea3c11d691712039addc4037943b257e9d7967'>spice.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/services/spice.scm?id=bcea3c11d691712039addc4037943b257e9d7967&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2017-01-25 14:05:37 +0100'>2017-01-25</span></td><td><a href='/guix/commit/gnu/services/spice.scm?id=e57bd0bed86caac304e5f37c5653e6b13858c7c5'>services: Fix 'mkdir-p' in activation scripts.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/cups.scm (%cups-activation): Import (guix build utils).
* gnu/services/mail.scm (opensmtpd-activation): Idem.
* gnu/services/networking.scm (ntp-service-activation): Idem.
* gnu/services/spice.scm (spice-vdagent-activation): Idem.
* gnu/services/ssh.scm (openssh-activation): Idem.
  (dropbear-activation): Idem.
* gnu/services/vpn.scm (%openvpn-activation): Idem.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Clément Lassieur</td></tr>
<tr><td><span title='2016-09-10 13:10:06 +0200'>2016-09-10</span></td><td><a href='/guix/commit/gnu/services/spice.scm?id=9e41130b14ad32c4e1fa756f95d806703056cb60'>system: Use 'file-append' to denote file names.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/avahi.scm, gnu/services/base.scm,
gnu/services/databases.scm, gnu/services/dbus.scm,
gnu/services/desktop.scm, gnu/services/dict.scm,
gnu/services/mail.scm, gnu/services/networking.scm,
gnu/services/sddm.scm, gnu/services/spice.scm,
gnu/services/ssh.scm, gnu/services/web.scm,
gnu/services/xorg.scm, gnu/system.scm: Replace the
 #~(string-append #$pkg "/bin/foo") idiom with
 (file-append pkg "/bin/foo").
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-08-05 21:48:43 +0200'>2016-08-05</span></td><td><a href='/guix/commit/gnu/services/spice.scm?id=00f469056893ae80fecefee44e09d6904b613de4'>services: Add spice vdagent service.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/spice.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* doc/guix.texi (Various Services): New subheading.
</span></span></td><td>David Craven</td></tr>