Deprecated: Function get_currentuserinfo is deprecated since version 4.5.0! Use wp_get_current_user() instead. in /var/www/html/wp-includes/functions.php on line 5383
this is not envisaged in the back-end of the theme (as a ready-made feature), but in principle this effect can be achieved by setting the “position” property of the menu element as “fixed”, in which case it will stay where it is regardless of the scroll.