title: iOS Safari font-kerning/letter-spacing issue for Avenir
body: <p>There is a weird behaviour in iOS Safari where a specific font-weight of 900 for Avenir font produces an extra space on the right of characters <code>fi</code>.  </p>
  
  <p><a href="https://i.stack.imgur.com/prJdZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/prJdZ.png" alt="Weird space after fi"></a><br>
  <a href="https://i.stack.imgur.com/QD8gY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QD8gY.png" alt="enter image description here"></a></p>
  
  <p>I tried using 'Avenir Heavy' which corresponds to that font-weight but the issue is is still apparent. It does not appear on any other font-weights though, just on that 900 weight. I tried playing around <code>-webkit-font-kerning</code>, <code>-webkit-font-smoothing</code>, <code>letter-spacing</code>, but none solves the issue.</p>
  
  <p>Is there a CSS-only way of working around this? Or is this an issue on the font/browser itself?</p>
  
  <p>Thanks.</p>