If you have configured the Confluence URL as http://confluence.yourdomain.com, but access it as https://confluence.yourdomain.com then the

macro does not display live search results (clicking on ok works though).

FireFox displays the error message "Fehler: uncaught exception: Die Erlaubnis für den Aufruf der Methode XMLHttpRequest.open wurde verweigert" which is something like "uncaught exception: it is not permitted to execute XMLHttpRequest.open". This error message is generated whenever the xml request url does not match the actual website url.

It works correct when accessed as http://... or when the Confluence domain is set to https://...

The fix would be to modify this request so that the request actually matches the current access method.