diff --git a/js/ui/status/keyboard.js b/js/ui/status/keyboard.js
index 883c534b8..ae498e0f9 100644
--- a/js/ui/status/keyboard.js
+++ b/js/ui/status/keyboard.js
@@ -71,7 +71,7 @@ XKBIndicator.prototype = {
 
         this.menu.addMenuItem(new PopupMenu.PopupSeparatorMenuItem());
         this.menu.addAction(_("Show Keyboard Layout..."), Lang.bind(this, function() {
-            Util.spawn(['gkbd-keyboard-display', '-g', this._config.get_current_group() + 1]);
+            Util.spawn(['gkbd-keyboard-display', '-g', String(this._config.get_current_group() + 1)]);
         }));
         this.menu.addAction(_("Localization Settings"), function() {
             Util.spawn(['gnome-control-center', 'region']);