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функция не описана

Bulk_Upgrader_Skin::add_strings() public WP 1.0

Это метод класса: Bulk_Upgrader_Skin{}

Хуков нет.

Возвращает

Null. Ничего.

Использование

$Bulk_Upgrader_Skin = new Bulk_Upgrader_Skin();
$Bulk_Upgrader_Skin->add_strings();

Код Bulk_Upgrader_Skin::add_strings() WP 5.5.1

wp-admin/includes/class-bulk-upgrader-skin.php
<?php
public function add_strings() {
	$this->upgrader->strings['skin_upgrade_start'] = __( 'The update process is starting. This process may take a while on some hosts, so please be patient.' );
	/* translators: 1: Title of an update, 2: Error message. */
	$this->upgrader->strings['skin_update_failed_error'] = __( 'An error occurred while updating %1$s: %2$s' );
	/* translators: %s: Title of an update. */
	$this->upgrader->strings['skin_update_failed'] = __( 'The update of %s failed.' );
	/* translators: %s: Title of an update. */
	$this->upgrader->strings['skin_update_successful'] = __( '%s updated successfully.' );
	$this->upgrader->strings['skin_upgrade_end']       = __( 'All updates have been completed.' );
}