diff --git a/ccp/js/methodeditorcontroller.js b/ccp/js/methodeditorcontroller.js
index 8740f1b..f3591a8 100644
--- a/ccp/js/methodeditorcontroller.js
+++ b/ccp/js/methodeditorcontroller.js
@@ -258,7 +258,7 @@ class CCPMethodEditorController extends HTMLElement {
           format: "url",
           contentMediaType: "text/plain",
           default: "",
-          readonly: true,
+          readOnly: true,
         }
       }
     ]