fix: the enabled prop isn't actually needed

content/install-hook-openusercss.js

@@ -81,7 +81,6 @@ const sendInstallCallback = data => {
   allowedOrigins.forEach(origin => {
     window.postMessage({
       'type': 'ouc-install-callback',
-      'enabled': data.enabled,
       'key':  data.key
     }, origin);
   });