Some applications will use an HTTP header, 'X-frame-options'. When the value is 'deny', CRW will rightly refuse to show the application page in the pane in the right hand side of the window.

This header is associated with Spring applications [1].

Can the CRW user be warned that this is the reason they cannot see the application in the right-hand pane?

[1] https://stackoverflow.com/questions/28647136/how-to-disable-x-frame-options-response-header-in-spring-security