title: How to remove border from dropdown tab in bootstrap navbar
body: <p>using Bootstrap 4, I cannot seem to get rid of this border when selecting the drop-down tab.</p>
  
  <p><a href="https://i.stack.imgur.com/lo1qd.png" rel="nofollow noreferrer">Problem</a></p>
  
  <p><a href="https://i.stack.imgur.com/wyR5q.png" rel="nofollow noreferrer">Inspector View</a></p>
  
  <p><a href="https://i.stack.imgur.com/HPgOk.png" rel="nofollow noreferrer">Code</a></p>