title: How to add subviews to a UIButton via Storyboard?
body: <p>Is it not possible to add a subview to a UIButton via Storyboard? <a href="https://stackoverflow.com/questions/19704755/adding-a-subview-to-uibutton">This answer</a> suggests it is possible in code, but how do you do it via Storyboard? Dragging a UIView to become a child of a UIButton isn't working.</p>
  
  <p>Aware of simple workarounds like creating a parent UIView to hold the UIButton and subviews, but this question focuses on whether it's possible to add subviews to a UIButton inside of Storyboard.</p>