diff --git a/addons/website/static/src/js/widgets/theme.js b/addons/website/static/src/js/widgets/theme.js
index 8b659c0ff22..9fc2f0e1c21 100644
--- a/addons/website/static/src/js/widgets/theme.js
+++ b/addons/website/static/src/js/widgets/theme.js
@@ -31,6 +31,7 @@ var ThemeCustomizeDialog = Dialog.extend({
         options = options || {};
         this._super(parent, _.extend({
             title: _t("Customize this theme"),
+            buttons: [],
         }, options));
 
         this.defaultTab = options.tab || 0;