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событие не описано

activate_wp_head хук-событие . WP 3.0.0

Fires before the Site Activation page is loaded.

Fires on the {@see 'wp_head'} action.

Использование

add_action( 'activate_wp_head', 'action_function_name_6172' );
function action_function_name_6172(){
	// action...
}

Связи хука

Используется в: do_activate_header()

Кусок кода с хуком

Фрагмент из: wp-activate.php WP 4.9
...
/**
 * Adds an action hook specific to this page.
 *
 * Fires on {@see 'wp_head'}.
 *
 * @since MU (3.0.0)
 */
function do_activate_header() {
	/**
	 * Fires before the Site Activation page is loaded.
	 *
	 * Fires on the {@see 'wp_head'} action.
     *
     * @since 3.0.0
     */
    do_action( 'activate_wp_head' );
}
add_action( 'wp_head', 'do_activate_header' );

/**
 * Loads styles specific to this page.
 *
 * @since MU (3.0.0)
 */
function wpmu_activate_stylesheet() {
	?>
	<style type="text/css">
		form { margin-top: 2em; }
		#submit, #key { width: 90%; font-size: 24px; }
		#language { margin-top: .5em; }
		.error { background: #f66; }
...