title: How to us proxy with chromedp
body: <p>I want to take screenshot of (thousands of pages) of website like Amazon. I tried some code but getting captcha or traffic error in screenshot. So I want to add proxy with chromedp.</p>
  
  <pre class="lang-golang prettyprint-override"><code>ctx, cancel := chromedp.NewContext(context.Background())
  defer cancel()
  chromedp.ProxyServer("http://username:password@proxyserver.com:31280")
  chromedp.Run(ctx,
          chromedp.Navigate("http://wtfismyip.com"),
          chromedp.Sleep(3*time.Second),
          chromedp.ActionFunc(func(ctxt context.Context) error {
              _, _, contentRect, err := page.GetLayoutMetrics().Do(ctxt)
              v := page.Viewport{
                  X:      contentRect.X,
                  Y:      contentRect.Y,
                  Width:  contentRect.Width,
                  Height: contentRect.Height,
                  Scale:  1,
              }
              buf, err := page.CaptureScreenshot().WithClip(&amp;v).Do(ctxt)
              log.Printf("Write %v", "/tmp/ss.png")
              ioutil.WriteFile("/tmp/ss.png", buf, 0644)
              return err
          }))
  </code></pre>
  
  <p>Tried this as well but not working.</p>