title: HTML Background image changes size when scrollbar appears
body: <p>I'm using this background image on all pages of my website:</p>
  
  <pre><code>body {
      background-image:url('...');
      background-attachment: fixed;
      background-repeat: no-repeat;
      background-size: cover;
  }
  </code></pre>
  
  <p>This works perfectly per single page. However, when switching between pages with and without a vertical scroll bar, the page width changes, and this causes the background image to change in size slightly to scale accordingly.</p>
  
  <p>This small transition is unpleasant, and I would like to avoid it. How would I do that? I there a way to let the background image 'ignore' the space taken by the scroll bar?</p>