When a content ACL is set to "registred" if a user try to access, it only get the red warning "You are not authorised to view this resource." without any prompting.
How can we custom this error message/section ? We use an external SSO plug-in, so we need to customize this rendering for adding a link to this SSO. We have try through the error.php file but the 403 error code is not detected :-/