wp_customize_support_script()

3795function wp_customize_support_script() {3796	$admin_origin = parse_url( admin_url() );3797	$home_origin  = parse_url( home_url() );3798	$cross_domain = ( strtolower( $admin_origin['host'] ) !== strtolower( $home_origin['host'] ) );3799	ob_start();3800	?>3801	<script>3802		(function() {3803			var request, b = document.body, c = 'className', cs = 'customize-support', rcs = new RegExp('(^|\\s+)(no-)?'+cs+'(\\s+|$)');3804 3805	<?php	if ( $cross_domain ) : ?>3806			request = (function(){ var xhr = new XMLHttpRequest(); return ('withCredentials' in xhr); })();3807	<?php	else : ?>3808			request = true;3809	<?php	endif; ?>3810 3811			b[c] = b[c].replace( rcs, ' ' );3812			// The customizer requires postMessage and CORS (if the site is cross domain).3813			b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;3814		}());3815	</script>3816	<?php3817	wp_print_inline_script_tag( wp_remove_surrounding_empty_script_tags( ob_get_clean() ) . "\n//# sourceURL=" . rawurlencode( __FUNCTION__ ) );3818}