Prints a script to check whether or not the Customizer is supported, and apply either the no-customize-support or customize-support class to the body.
This function MUST be called inside the body tag.
Ideally, call this function immediately after the body tag is opened. This prevents a flash of unstyled content.
It is also recommended that you add the "no-customize-support" class to the body tag by default.
File: wp-includes/theme.php
function wp_customize_support_script() {
$admin_origin = parse_url( admin_url() );
$home_origin = parse_url( home_url() );
$cross_domain = ( strtolower( $admin_origin['host'] ) != strtolower( $home_origin['host'] ) );
$type_attr = current_theme_supports( 'html5', 'script' ) ? '' : ' type="text/javascript"';
?>
<script<?php echo $type_attr; ?>>
(function() {
var request, b = document.body, c = 'className', cs = 'customize-support', rcs = new RegExp('(^|\\s+)(no-)?'+cs+'(\\s+|$)');
<?php if ( $cross_domain ) : ?>
request = (function(){ var xhr = new XMLHttpRequest(); return ('withCredentials' in xhr); })();
<?php else : ?>
request = true;
<?php endif; ?>
b[c] = b[c].replace( rcs, ' ' );
// The customizer requires postMessage and CORS (if the site is cross domain).
b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;
}());
</script>
<?php
} | Version | Description |
|---|---|
| 5.5.0 | IE8 and older are no longer supported. |
| 4.7.0 | Support for IE8 and below is explicitly removed via conditional comments. |
| 3.4.0 | Introduced. |
© 2003–2019 WordPress Foundation
Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/wp_customize_support_script