title: CATransaction synchronize called within transaction
body: <p>My app was working fine, displaying lines from an HTML file in a UITableView, but after updating some PODs the app crashes during startup and I receive this error and XCode doesn't show the exact line or function in which this error happens:</p>
  
  <pre><code>[CATransaction synchronize] called within transaction
  </code></pre>
  
  <p>The only thing I updated is HTMLKit.</p>