title: jspdf doesn't work when loaded from a CDN
body: <p>I am going to use package(<a href="https://github.com/parallax/jsPDF" rel="nofollow noreferrer">jspdf</a>) loaded from **CDN **</p>
  <p>this is CDN</p>
  <pre><code>&lt;script src=&quot;https://cdnjs.cloudflare.com/ajax/libs/jspdf/2.5.1/jspdf.umd.min.js&quot;&gt;&lt;/script&gt;
  </code></pre>
  <p>and I have <strong>loaded</strong> it like this in a page :</p>
  <pre class="lang-js prettyprint-override"><code>mounted() {
    if (document.getElementById('myScript')) { return }
    let src = 'https://cdnjs.cloudflare.com/ajax/libs/jspdf/2.5.1/jspdf.umd.min.js'
    let script = document.createElement('script')
    script.setAttribute('src', src)
    script.setAttribute('type', 'text/javascript')
    script.setAttribute('id', 'myScript')
    document.head.appendChild(script)
  }
  </code></pre>
  <p>and I have a <strong>button</strong> that when you <strong>click</strong> on it a below <strong>method</strong> will called and some pdf will be generated.</p>
  <pre class="lang-js prettyprint-override"><code>generateReport() {
    var doc = new jsPDF('l', 'mm', [62, 32])
    const margins = {
      top: 0,
      bottom: 60,
      left: 0,
      width: 122
    }
  
    doc.fromHTML(this.$refs.print, margins.left, margins.top, {
      width: margins.width
    })
  
    doc.save('test.pdf')
  }
  </code></pre>
  <p><strong>BUT</strong> I get an error</p>
  <p><a href="https://i.stack.imgur.com/axF5W.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/axF5W.png" alt="enter image description here" /></a></p>
  <p>So, how can I <strong>fix</strong> this error?</p>