WordPress at a glance
action is not described

customize_register action-hook . WP 3.4.0

Fires once WordPress has loaded, allowing scripts and styles to be initialized.

Usage

add_action( 'customize_register', 'action_function_name_9931' );
function action_function_name_9931( $this ){
	// action...
}
$this(WP_Customize_Manager)
WP_Customize_Manager instance.

Where the hook is called

WP_Customize_Manager::wp_loaded()
_wp_customize_publish_changeset()
wp-includes/class-wp-customize-manager.php 926
do_action( 'customize_register', $this );
wp-includes/theme.php 2904
do_action( 'customize_register', $wp_customize );

Where the hook is used (in WP core)

wp-includes/class-wp-customize-widgets.php 105
add_action( 'customize_register', array( $this, 'schedule_customize_register' ), 1 );
wp-includes/class-wp-customize-nav-menus.php 49
add_action( 'customize_register', array( $this, 'customize_register' ), 11 );
wp-includes/theme.php 2900
remove_action( 'customize_register', array( $wp_customize, 'register_controls' ) );
wp-includes/class-wp-customize-manager.php 387
add_action( 'customize_register', array( $this, 'register_controls' ) );
wp-includes/class-wp-customize-manager.php 388
add_action( 'customize_register', array( $this, 'register_dynamic_settings' ), 11 ); // allow code to create settings first
wp-includes/class-wp-customize-manager.php 1568
add_action( 'customize_register', array( $this, '_save_starter_content_changeset' ), 1000 );