The Content Security Policy is a powerful security header, which allows fine-grained control over the (types of) resources that your site is allowed to load. The Policy is sent to the visitor’s browser as ‘instructions’ on what type of content may be loaded from which sources. Source Directives are used to specify types of content and sources to be allowed. All resources not included into the Content Security Policy will be blocked.
Really Simple SSL Pro allows site administrators to easily generate a Content Security Policy. After a learning mode interval, the site administrator is able to allow or revoke source directives via the Source Directives interface.