title: IntelliJ IDEA plugin for JavaFX Scene Builder drag & drop stops working
body: <p>I'm working with IDEA Ultimate 2016.3, Scene Builder 2.0-b20 on MacOS Sierra.</p>
  
  <p>The drag &amp; drop feature, dragging the controls from the left side panel into the scene seems to stop working after a while. I have to restart IDEA when this happens before they start working again.</p>
  
  <p>Any pointers on why this happens or how to resolve it without having to re-start IDEA are appreciated.</p>
  
  <p>I've attached a screenshot in case the explanation wasn't good enough.</p>
  
  <p><a href="https://i.stack.imgur.com/Yj1uk.png" rel="noreferrer"><img src="https://i.stack.imgur.com/Yj1uk.png" alt="Scene Builder"></a></p>