title: Navigation Controller popToRootController() followed by pushing controllers UI bug
body: <p>In my app I'm currently calling navigationController.popToRootController() followed by immediately pushing a few controllers onto the stack, but it's causing a weird UI bug. Instead of appearing from the left side, the new controller being presented appears from bottom up, and the weird thing is the navigation bar at the top of the screen is completely gone. Can't navigate back, can't interact with any of the navigation items ... just gone. Wondering if it has to do with popping to the root controller then immediately trying to push new controllers that could cause this weird bug. Hope someone has an insight into this. Thanks!</p>
  
  <p>fileList is a navigation controller</p>
  
  <pre><code>fileList.popToRootController()
  fileList.clearList()
  var isRoot = true
  for file in (deepLinkFolder?.fileList)! {
      // push file controller onto navigation controller (fileList)
  }
  </code></pre>