To link menu to an external URL,
Go to the Menu Configuration screen.
Select the hierarchical position for your smart form and click on the icon. It opens the Menu Properties screen.
Enter the details for Description & Sequence
Enter the full path for your external URL
Choose the Type as PAGE
Click OK.
Click on Save Menu button in the Menu Configurations Screen
Logout and Login to ONEWEB and the menu is ready to use.
Note: Please make sure to enable Cross Origin Resource Sharing on the browser to load the external URL within your application.