Allow HTML in the product description

function wcv_wpkses_post_html_tags( $tags, $context ) {

	if ( 'post' === $context ) {

		$tags['iframe'] = array(

			'src'             => true,

			'height'          => true,

			'width'           => true,

			'frameborder'     => true,

			'allowfullscreen' => true,

		);

	}

	return $tags;

}

add_filter( 'wp_kses_allowed_html', 'wcv_wpkses_post_html_tags', 10, 2 );