wp_customize_support_script()

3808function wp_customize_support_script() {3809	$admin_origin = parse_url( admin_url() );3810	$home_origin  = parse_url( home_url() );3811	$cross_domain = ( strtolower( $admin_origin['host'] ) !== strtolower( $home_origin['host'] ) );3812	ob_start();3813	?>3814	<script>3815		(function() {3816			var request, b = document.body, c = 'className', cs = 'customize-support', rcs = new RegExp('(^|\\s+)(no-)?'+cs+'(\\s+|$)');3817 3818	<?php	if ( $cross_domain ) : ?>3819			request = (function(){ var xhr = new XMLHttpRequest(); return ('withCredentials' in xhr); })();3820	<?php	else : ?>3821			request = true;3822	<?php	endif; ?>3823 3824			b[c] = b[c].replace( rcs, ' ' );3825			// The customizer requires postMessage and CORS (if the site is cross domain).3826			b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;3827		}());3828	</script>3829	<?php3830	wp_print_inline_script_tag( wp_remove_surrounding_empty_script_tags( ob_get_clean() ) . "\n//# sourceURL=" . rawurlencode( __FUNCTION__ ) );3831}