JSFiddle - React, Tailwind, and code Playground

HTML

<div class="dummy"></div>

JavaScript

(function ($) {
    $(function() {
        $('.dummy').data('foo', 'bar');
        $.each($.cache, function (k, v) {
            if (v.foo) {
                $('body').append($('<div>found foo: ' + v.foo + ' at index ' + k + '</div>'));
            }
        });
    });
}(jQuery));