To support cross-domain tracking/iframe setups please always append the Freespee sessionID from the parent page into the iframe URL by adding the “__fs_dncs_sessionid” parameter at the end of the URL. 

How to activate

It could look something like this:

if (window.__fs_dncs_instance) {
     urlIframe = "http://some.url.com/?__fs_dncs_sessionid=" + __fs_dncs_instance.getSessionId();
}