YARN-5779. [YARN-3368] Addendum patch to document limits/notes of the new YARN UI . (Sunil G via Sreenath Somarajapuram)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/YarnUI2.md

@@ -38,6 +38,9 @@ origin (CORS) support.
 | `yarn.resourcemanager.webapp.cross-origin.enabled` | true | Enable CORS support for Resource Manager  |
 | `yarn.nodemanager.webapp.cross-origin.enabled` | true | Enable CORS support for Node Manager  |
 
+Also please ensure that CORS related configurations are enabled in `core-site.xml`.
+Kindly refer [here](https://hadoop.apache.org/docs/stable/hadoop-project-dist/hadoop-common/HttpAuthentication.html)
+
 Use it
 -------------
 Open your browser, go to `rm-address:8088/ui2` and try it!