diff --git a/addons/website/static/src/components/dialog/page_properties.js b/addons/website/static/src/components/dialog/page_properties.js
index 273ebb7bdf0..57258ca2541 100644
--- a/addons/website/static/src/components/dialog/page_properties.js
+++ b/addons/website/static/src/components/dialog/page_properties.js
@@ -139,7 +139,7 @@ DuplicatePageDialog.template = xml`
 </WebsiteDialog>
 `;
 DuplicatePageDialog.props = {
-    onDuplicate: {type: Function, optional: true},
+    onDuplicate: Function,
     close: Function,
     pageId: Number,
 };