title: ReferenceError: vis is not defined
body: <p>I installed vis.js through npm <code>npm install vis-network</code></p>
  <p>and already require it in my <code>app.js</code></p>
  <pre><code>try {
      require('vis-network');
  } catch (e) { }
  </code></pre>
  <p>and recompiled it in laravel mix</p>
  <pre><code>npm run dev
  </code></pre>
  <p>but whenever I instantiate a vis instance I always get <code>vis is not define</code> error on console..</p>
  <pre><code>&lt;script&gt;
  let nodes = new vis.DataSet(_nodes),
      edges = new vis.DataSet(_connections);
  
  ...
  let network = new vis.Network(container, { nodes: nodes, edges: edges }, _options);
  &lt;/script&gt;
  </code></pre>
  <p>What am I missing?</p>