Patch from NixOS retrieved from
https://raw.githubusercontent.com/NixOS/nixpkgs/master/pkgs/development/libraries/accountsservice/drop-prefix-check-extensions.patch.

diff --git a/src/extensions.c b/src/extensions.c
index 038dcb2..830465d 100644
--- a/src/extensions.c
+++ b/src/extensions.c
@@ -121,16 +121,7 @@ daemon_read_extension_directory (GHashTable  *ifaces,
                         continue;
                 }
 
-                /* Ensure it looks like "../../dbus-1/interfaces/${name}" */
-                const gchar * const prefix = "../../dbus-1/interfaces/";
-                if (g_str_has_prefix (symlink, prefix) && g_str_equal (symlink + strlen (prefix), name)) {
-                        daemon_read_extension_file (ifaces, filename);
-                }
-                else {
-                        g_warning ("Found accounts service vendor extension symlink %s, but it must be exactly "
-                                   "equal to '../../dbus-1/interfaces/%s' for forwards-compatibility reasons.",
-                                   filename, name);
-                }
+                daemon_read_extension_file (ifaces, filename);
         }
 
         g_dir_close (dir);
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<div class='path'>path: <a href='/guix/log/?id=1f3921e1435db7c9489f22832554ad4692434efc'>root</a>/<a href='/guix/log/berlin.guixsd.org.pub?id=1f3921e1435db7c9489f22832554ad4692434efc'>berlin.guixsd.org.pub</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/berlin.guixsd.org.pub?id=1f3921e1435db7c9489f22832554ad4692434efc&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2017-12-04 17:57:37 +0100'>2017-12-04</span></td><td><a href='/guix/commit/berlin.guixsd.org.pub?id=be5622e7f1b2f4e4567214b209bfd153dfd59013'>maint: Add 'berlin.guixsd.org.pub'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>