title: Angular 2 Application reacting very slowly only while Chrome DevTools is open
body: <p>My Angular 2 Application is slow to respond (1-5 seconds) to key input, button clicks, tabbing across inputs, etc. <em>only</em> when Chrome Developer Tools is open.  Material 2 animations also become slow and choppy.</p>
  
  <p>I've been developing this application for three months, and use Chrome DevTools every day. This issue cropped up seemingly overnight.</p>
  
  <p>What I know:</p>
  
  <ul>
  <li>I stashed all pending application changes to revert my application to a time when this was not a problem.  The issue persisted.</li>
  <li>Chrome DevTools doesn't seem to slow down any other application (ie. google inbox, google maps) in the same browser session.</li>
  <li><strong>Maddeningly, when I run the DevTools' Timeline "Record" to try to gain visibility into the issue, the issue disappears and the page reacts at normal speed again!</strong>  I assume this is the best clue that I have, but I don't know the internal workings of DevTools well enough to know how "Timeline Record" changes things.</li>
  <li>I've restarted Chrome and deleted all cached data.</li>
  <li>Nothing of the sort happens in Firefox or IE when I open the Developer tools in those.</li>
  </ul>
  
  <p>Any recommendations on where to look next would be greatly appreciated!</p>