jQuery to allow Wordpress menu items to open sub-menus directly using mmenu

mmenu-wp-open-submenu.js

/*
mmenu (http://mmenu.frebsite.nl/) has a way to make a click on a menu item
open a sub-menu (as opposed to a click on the arrow to the right of the item).

See:
 http://mmenu.frebsite.nl/support/tips-and-tricks.html#tt-subopenlinks
 https://github.com/BeSite/jQuery.mmenu/issues/45

However, Wordpress menus by default do not allow an easy way
to use either of these techniques. This snippet modifies
the menu HTML generated by Wordpress / mmenu, 
and adds appropriate classes to any menu item
with a link starting with '#' to have that item
open the sub-menu directly.
*/

var $the_menu = $('.wp-menu-selector-here');
$the_menu.mmenu();
$the_menu
    .find("a:not(.mm-subopen)[href^='#']")
    .prev(".mm-subopen")
    .addClass("mm-fullsubopen ");