Includes and instantiates the WP_Customize_Manager class.

Loads the Customizer at plugins_loaded when accessing the customize.php admin page or when any request includes a wp_customize=on param or a customize_changeset param (a UUID). This param is a signal for whether to bootstrap the Customizer when WordPress is loading, especially in the Customizer preview or when making Customizer Ajax requests for widgets or menus.

Signature

_wp_customize_include()

Return

(void)

Source

function _wp_customize_include() {

	$is_customize_admin_page = ( is_admin() && 'customize.php' == basename( $_SERVER['PHP_SELF'] ) );
	$should_include = (
		$is_customize_admin_page
		||
		( isset( $_REQUEST['wp_customize'] ) && 'on' == $_REQUEST['wp_customize'] )
		||
		( ! empty( $_GET['customize_changeset_uuid'] ) || ! empty( $_POST['customize_changeset_uuid'] ) )
	);

	if ( ! $should_include ) {
		return;
	}

	/*
	 * Note that wp_unslash() is not being used on the input vars because it is
	 * called before wp_magic_quotes() gets called. Besides this fact, none of
	 * the values should contain any characters needing slashes anyway.
	 */
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