title: How to make Bootstrap 4 compatible with IE9 and IE10
body: <p>Which polyfill libaries can be used to make Bootstrap 4 (or most of Bootstrap 4) work with IE9?</p>
  
  <p>I've come across these libraries:</p>
  
  <ul>
  <li><a href="https://github.com/jonathantneal/flexibility" rel="noreferrer">https://github.com/jonathantneal/flexibility</a></li>
  <li><a href="https://github.com/coliff/bootstrap-ie8" rel="noreferrer">https://github.com/coliff/bootstrap-ie8</a></li>
  </ul>
  
  <p>Thanks.</p>