diff --git a/extensions/firefox-share/src/modules/panel.js b/extensions/firefox-share/src/modules/panel.js
index 84d26dc..8f456f0 100644
--- a/extensions/firefox-share/src/modules/panel.js
+++ b/extensions/firefox-share/src/modules/panel.js
@@ -104,17 +104,17 @@ sharePanel.prototype = {
       }
     }, false);
     this.loadListener = function (evt) {
+      self.attachMessageListener();
       self.window.setTimeout(function () {
         self.sizeToContent();
       }, 0);
     };
     this.browser.addEventListener("load", this.loadListener, true);
-    Services.obs.addObserver(this, 'content-document-global-created', false);
 
     let webProgress = this.browser.webProgress;
     this.stateProgressListener = new StateProgressListener(this);
     webProgress.addProgressListener(this.stateProgressListener, Ci.nsIWebProgress.NOTIFY_STATE_WINDOW);
-    
+
     // Extend Services object
     XPCOMUtils.defineLazyServiceGetter(
       Services, "bookmarks",
@@ -123,29 +123,13 @@ sharePanel.prototype = {
     );
   },
 
-  unload: function () {
-    Services.obs.removeObserver(this, 'content-document-global-created');
+  shutdown: function () {
     let webProgress = this.browser.webProgress;
     webProgress.removeProgressListener(this.stateProgressListener);
     this.stateProgressListener = null;
   },
 
-  observe: function (aSubject, aTopic, aData) {
-    if (!aSubject.location.href) {
-      return;
-    }
-
-    // is this window a child of OUR XUL window?
-    let mainWindow = aSubject.QueryInterface(Ci.nsIInterfaceRequestor)
-            .getInterface(Ci.nsIWebNavigation)
-            .QueryInterface(Ci.nsIDocShellTreeItem)
-            .rootTreeItem.QueryInterface(Ci.nsIInterfaceRequestor)
-            .getInterface(Ci.nsIDOMWindow);
-    mainWindow = mainWindow.wrappedJSObject ? mainWindow.wrappedJSObject : mainWindow;
-    if (mainWindow !== this.panel.ownerDocument.defaultView) {
-      return;
-    }
-
+  attachMessageListener: function () {
     // listen for messages now
     let self = this;
     let contentWindow = this.browser.contentWindow;
@@ -523,7 +507,7 @@ sharePanel.prototype = {
       return null;
     return url;
   },
-  
+
   previews: function () {
     // Look for FB og:image and then rel="image_src" to use if available
     // for og:image see: http://developers.facebook.com/docs/share