diff --git a/src/demo/js/script.js b/src/demo/js/script.js
index 00044a79..5e5b5e78 100644
--- a/src/demo/js/script.js
+++ b/src/demo/js/script.js
@@ -223,6 +223,7 @@ const preview = {
     const option = Array.prototype.find.call(selectElement.options, (o) => o.value === property);
     selectElement.disabled = false;
     option.disabled = false;
+    selectElement.value = option.value;
     // update and exit
     this.update();
   },