title: Is chrome.extension.onRequest deprecated?
body: <p>I'm building a chrome extension and attempting to attach an event listener to this, but I'm not seeing anything in the console of the background page.</p>
  
  <pre><code>chrome.extension.onRequest.addListener(function(request, sender, sendResponse) {
            console.log('REFERRER', request.ref);
          });
  </code></pre>
  
  <p>This code is in my main.js background page, all my other event listeners (chrome.tabs.onUpdated, chrome.extension.onMessage, etc) are all working fine though.</p>