JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://github.com/ehynds/jquery-ui-multiselect-widget/raw/1.7/src/jquery.multiselect.js"></script>
<link rel="stylesheet" href="http://github.com/ehynds/jquery-ui-multiselect-widget/raw/1.7/jquery.multiselect.css">
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.7/themes/base/jquery-ui.css">
<select multiple>
    <option value="foo">foo</option>
    <option value="bar">bar</option>
    <option value="baz">baz</option>
</select>

JavaScript

var widget = $("select").multiselect({
    selectedList: 1
}).multiselect("widget");

widget.find(":checkbox:eq(0)")[0].click();
widget.find(":checkbox:eq(1)")[0].click();