This feature does only work if the page is loaded from the SAME domain.. If you use the setting below no iframe is used anymore. So only include stuff that is for display only.
Please note: Loading the external content is done after the page is fully loaded and takes some time. Therefore some extra settings below are possible to make the integration as invisible as possible. The included div has the id ai_temp_>iframe_name<. So if you need to overwrite some css you can put it in an extra file and add this in the section "Additional files" ', 'advanced-iframe');
_e('
"Include html" does write the given string directly and all other settings are not used!', 'advanced-iframe'); echo '