Replace jQuery code with its implementation

Replace jQuery code with its implementation

Hello!

I am not sure if this belongs to "Using jQuery" forum, because I basically want to use the jQuery's implementation (pure JavaScript core) instead of jQuery. So, I have this plugin (the full code is available here ). In this plugin, I am using some jQuery code, because I don't know how I can get the same result with pure JavaScript, o your help will be appreciated.
  1. $(this._elem).click(function(e) {
  2.   e.stopPropagation();
  3.   $("[data-class=\"popup\"]").not(self._menu).hide();
  4.   $(self._menu).toggle();
  5. }