title: selenium c# chrome pdf validation
body: <p>With Selenium using C#, I'm trying to validate a PDF pops up in an app. My code to click the Close (X) button at the top-right of the PDF works, but not the code to verify any elements for the PDF, such as: </p>
  
  <pre><code>//*[@id="plugin"]
  </code></pre>
  
  <p>Basically, I'm not able to access any elements in the separate Developer Tools browser that opens up after using Inspect on the PDF. The element for the PDF Close button, which I am able to access, is in a separate Developer Tools browser.</p>
  
  <p>I've installed the PDF Viewer (PDF.js) Extension for Chrome. 
  I've also tried switching frames:</p>
  
  <pre><code>IWebDriver 
  driver.SwitchTo().Window(PropertiesCollection.driver.WindowHandles.Last())
  </code></pre>
  
  <p>No luck. Can someone share a working code snippet?</p>