Supports interaction with the MRAID host API within Ad webviews in mobile apps
<script async custom-element="amp-mraid" src="https://cdn.ampproject.org/v0/amp-mraid-0.1.js"></script>
amp-mraid extension is included in an AMPHTML ad it will load
mraid.js and register MRAID functions as host services. This allows
amp-lightbox to operate in mobile app ads.
amp-mraid extension is intended for AMPHTML
ads. It is intended to be
injected by the ad network after validation, and as such a creative with
amp-mraid will not validate.