title: Chrome Developer Tools closes instantly when attempting to debug WebDriver E2E test
body: <p>I usually debug my Selenium tests in Chrome's dev tools panel. However, after upgrading my OS (Ubuntu Linux), my E2E tests broke completely: Chrome didn't open the first page, but sat idle showing only a blank page. Eventually I upgraded <a href="https://code.google.com/p/selenium/wiki/ChromeDriver">ChromeDriver</a>, and now the tests work again. But with this new Chrome version (after the OS upgrade) and with this new ChromeDriver, there's a weird problem with the dev tools window:</p>
  
  <p>Whenever I click <em>CTRL + SHIFT + I</em> to open the dev tools window, or click <em>Tools -> Developer Tools</em> in Chrome's menu, the dev tools window flashes open, but then closes instantly. It looks blank and empty, the 1/10 seconds it's visible. This has really never happened before.</p>
  
  <p>When I manually open another tab in [the Chrome instance that's being driven by WebDriver], and navigate to e.g. <em><a href="http://www.google.se/">http://www.google.se/</a></em>, then, when I open the dev tools window in that tab, it usually stays open (but not always). — It's mainly [the dev tools window for the browser tab that is being controlled by the Chrome Driver] that closes instantly.</p>
  
  <p>However if I hold town CTRL+SHIFT+I for a while, this genereates many many "clicks", and then the dev tools suddenly stays open, sometimes. But after 10-20 seconds it suddenly closes again.</p>
  
  <p>Why is Chrome doing this? How can I have it stop?</p>
  
  <p><sub>Chrome Version 29.0.1547.57<br>
  Chrome Driver versions 2.0, 2.1 and 2.2 tested (and problem present).<br>
  Selenium 2.35.0, and version 2.25.0 (I think it was) also didn't work.
  </sub></p>