JSFiddle - React, Tailwind, and code Playground

HTML

<select id="menu" name="menu">
    <option value="http://heise.de">HEISE</option>
    <option value="http://golem.de">Golem</option>
</select>

JavaScript

var sel = document.getElementById('menu');
sel.onchange = function() {
    window.location.href = this.value;
}