title: Selenium test hangs on css transition when chrome window is sent to background on mac
body: <p>I'm experiencing an annoying issue while running my behat selenium tests on my mac, El capitan. </p>
  
  <p>I have a test that opens a modal that will hang if the chrome window is behind another window. As soon as I click on the chrome window to bring it to the front, the test continues and passes. </p>
  
  <p>The modal uses a css transition to show. If I remove the transition, the test passes. If I keep a portion of the browser visible, the test passes.</p>
  
  <p>I'm unsure if this is mac doing some kind of performance optimization or chrome. Anyone know of a way I can disable this? I'd rather not have to disable css transitions or run chrome headless.</p>