title: How can I use window print in modal vue?
body: <p>My vue component like this :</p>
  
  <pre><code>&lt;template&gt;
      ...
      &lt;b-modal id="modalInvoice" size="lg"  title="Invoice"&gt;
          &lt;Invoice/&gt;
          &lt;div slot="modal-footer" class="w-100"&gt; 
              &lt;b-btn size="sm" class="float-right" variant="warning" @click="show=false"&gt;
                  &lt;i class="fa fa-print"&gt;&lt;/i&gt; Print
              &lt;/b-btn&gt;
          &lt;/div&gt;
      &lt;/b-modal&gt;
  
      ...
          &lt;b-btn variant="warning" class="btn-square mt-2" v-b-modal.modalInvoice @click="checkout()"&gt;&lt;i class="fa fa-credit-card-alt"&gt;&lt;/i&gt;Checkout&lt;/b-btn&gt;
      ...
  &lt;/template&gt;
  &lt;script&gt;
      ...
      export default {
          ...
          methods: {
              print() {
                  window.print()
              }
          }
      }
  &lt;/script&gt;
  </code></pre>
  
  <p>If I click print button, it works. But it displays the entire website. I just want if I click the print button, it only shows the contents of the modal</p>
  
  <p>How can I do it?</p>