From c73704ba483c9e1c799b24bb451cba5ae43dcf73 Mon Sep 17 00:00:00 2001
From: gorhill <rhill@raymondhill.net>
Date: Thu, 28 May 2015 14:49:36 -0400
Subject: [PATCH] code review

---
 platform/firefox/frameModule.js |  9 +++++++--
 platform/firefox/frameScript.js | 11 ++++++++++-
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/platform/firefox/frameModule.js b/platform/firefox/frameModule.js
index db7ce6f41..2e9c52ba8 100644
--- a/platform/firefox/frameModule.js
+++ b/platform/firefox/frameModule.js
@@ -218,7 +218,13 @@ const contentObserver = {
             });
 
             sandbox.injectScript = function(script) {
-                Services.scriptloader.loadSubScript(script, sandbox);
+                if ( Services !== undefined ) {
+                    Services.scriptloader.loadSubScript(script, sandbox);
+                } else {
+                    // Sandbox appears void.
+                    // I've seen this happens, need to investigate why.
+                    
+                }
             };
         }
         else {
@@ -358,7 +364,6 @@ LocationChangeListener.prototype.onLocationChange = function(webProgress, reques
     if ( !webProgress.isTopLevel ) {
         return;
     }
-
     this.messageManager.sendAsyncMessage(locationChangedMessageName, {
         url: location.asciiSpec,
         flags: flags,
diff --git a/platform/firefox/frameScript.js b/platform/firefox/frameScript.js
index e8c3cba41..388c7913b 100644
--- a/platform/firefox/frameScript.js
+++ b/platform/firefox/frameScript.js
@@ -56,7 +56,16 @@ let onLoadCompleted = function() {
 
 addMessageListener('ublock-load-completed', onLoadCompleted);
 
-locationChangeListener = new LocationChangeListener(docShell);
+if ( docShell ) {
+    let Ci = Components.interfaces;
+    let wp = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
+                     .getInterface(Ci.nsIWebProgress);
+    let dw = wp.DOMWindow;
+
+    if ( dw === dw.top ) {
+        locationChangeListener = new LocationChangeListener(docShell);
+    }
+}
 
 /******************************************************************************/