Bug 1659149 - add about:pioneer as a secure page in Firefox r=jaws

Differential Revision: https://phabricator.services.mozilla.com/D87116

browser/base/content/browser-siteIdentity.js

@@ -57,7 +57,7 @@ var gIdentityHandler = {
    * RegExp used to decide if an about url should be shown as being part of
    * the browser UI.
    */
-  _secureInternalPages: /^(?:accounts|addons|cache|certificate|config|crashes|downloads|license|logins|preferences|protections|rights|sessionrestore|support|welcomeback)(?:[?#]|$)/i,
+  _secureInternalPages: /^(?:accounts|addons|cache|certificate|config|crashes|downloads|license|logins|preferences|protections|rights|sessionrestore|support|welcomeback|pioneer)(?:[?#]|$)/i,
 
   /**
    * Whether the established HTTPS connection is considered "broken".