update config file with an option to disable the restriction on external http requests.

data/lightdm-webkit2-greeter.conf

@@ -1,14 +1,16 @@
 #
 # [greeter]
-# webkit-theme = Webkit theme to use.
 # debug_mode          = Greeter theme debug mode.
+# secure_mode         = Don't allow themes to make non-local http requests.
 # screensaver-timeout = Blank the screen after this many seconds of inactivity.
+# webkit-theme        = Webkit theme to use.
 #
 
 [greeter]
-webkit-theme = antergos
 debug_mode          = false
+secure_mode         = true
 screensaver-timeout = 300
+webkit-theme        = antergos
 
 #
 # [branding]
@@ -16,6 +18,8 @@ screensaver-timeout = 300
 # user_image        = Default user image/avatar. This is used by themes for users that have no .face image.
 # background_images = Path to directory that contains background images for use by themes.
 #
+# NOTE: Paths must be accessible to the lightdm system user account (so they cannot be anywhere in /home)
+#
 
 [branding]
 logo              = /usr/share/lightdm-webkit/themes/antergos/img/antergos.png

src/greeter.c

@@ -68,6 +68,7 @@ static gint config_timeout;
 
 static gboolean
 	debug_mode,
+	secure_mode,
 	heartbeat,
 	heartbeat_exit;