title: I can not quit Unity Editor, only force quit
body: <blockquote>
  <p>OS X 10.11.5</p>
  <p>Unity 5.3.4p1</p>
  </blockquote>
  <p>Every time I use command + q to quit my project or File-&gt; Open Project, Unity stop working, it seems everything is freezed with mac loading ball below.</p>
  <p>The only way out is to force quit.</p>
  <p>Can you help me? Can you just give me a way to solve this</p>
  <p>This really makes me crazy!!!</p>
  <p><a href="https://i.stack.imgur.com/1NjNn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1NjNn.png" alt="enter image description here" /></a></p>