function setupIframeScrollPrevention() {

		if( dom.slides.querySelector( 'iframe' ) ) {
			setInterval( function() {
				if( dom.wrapper.scrollTop !== 0 || dom.wrapper.scrollLeft !== 0 ) {
					dom.wrapper.scrollTop = 0;
					dom.wrapper.scrollLeft = 0;
				}
			}, 500 );
		}

	}
This is an unfortunate necessity. Iframes can trigger the
parent window to scroll, for example by focusing an input.
This scrolling can not be prevented by hiding overflow in
CSS so we have to resort to repeatedly checking if the
browser has decided to offset our slides :(