apply_filters( 'wpmu_signup_blog_notification', string|false $domain, string $path, string $title, string $user_login, string $user_email, string $key, array $meta )

958	 * @param string       $title      Site title.959	 * @param string       $user_login User login name.960	 * @param string       $user_email User email address.961	 * @param string       $key        Activation key created in wpmu_signup_blog().962	 * @param array        $meta       Signup meta data. By default, contains the requested privacy setting and lang_id.963	 */964	if ( ! apply_filters( 'wpmu_signup_blog_notification', $domain, $path, $title, $user_login, $user_email, $key, $meta ) ) {965		return false;966	}967 968	// Send email with activation link.969	if ( ! is_subdomain_install() || get_current_network_id() !== 1 ) {970		$activate_url = network_site_url( "wp-activate.php?key=$key" );