friendly iframeとは A Friendly IFrame is an IFrame that shares the same domain as the main page it is hosted on. This generally means that the content is trusted and hence, >can ‘break out’ of the IFrame and manipulate the content on the hosting page. Friendly IFrame is some kind of interactive and communicating frame. Adform | Friendly and non-Friendly IFrames とのことで、親ページと同じオリジンのiframe。これはsrcを指定しないで