title: extension using background, content and devtools together
body: <p>I've been trying to figure this out from the docs and samples but there just isn't enough there yet (or maybe I'm missing something?).</p>
  
  <p>I want to create a devtools panel but I still want access to the inspected window's dom like I get in content scripts. Right now my option is eval something in the context of the inspected window, but i would really rather not do that if I can avoid it. If I can just use a content script along with my devtools page/scripts that would be idea, but it doesn't seem to be working like I expect that it should - i can't seem to use the background page to send messages between my devtools page and my content script.</p>
  
  <p>Also, is there a way to get those cool dom subtrees to display like they do in the elements panel or in the console along with the awesome hover/highlight feature?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>So I can connect to the content script from the panel page by forwarding the tab id of the inspected window and pulling that out in my background page. So I have to do this</p>
  
  <pre><code>// devtools.js
  chrome.extension.sendMessage({ 
      'to': chrome.devtools.inspectedWindow.tabId, 
      'message': 'whatever'
  });
  </code></pre>
  
  <p>and </p>
  
  <pre><code>//background.js
  chrome.extension.onMessage.addListener(function(message,sender,callback) {
      message.from = sender.tab.id;
      chrome.tabs.sendMessage(message.to, message, callback);
  });
  </code></pre>
  
  <p>And my content.js script gets the message just fine ... and i thought that the sender's tab id would work to send things back from the content script, but it doesn't. The background script gets the message but the devtools page never gets it back.</p>
  
  <p>I'm having a bit of trouble figuring out how to properly debug devtools extensions as well. The content script can log to the page's console and the background script logs to the background page that you can inspect from the extensions page, but where does the devtools page log to?</p>