 
     deinit {
         NSNotificationCenter.defaultCenter().removeObserver(self)
+        self.webView.stopLoading()
+        self.webView.delegate = nil
     }
 
     override func viewWillAppear(animated: Bool) {

        backButtonItem?.enabled = webView.canGoBack
        forwardButtonItem?.enabled = webView.canGoForward
        titleLabel.text = currentValidURL().absoluteString
    }

    // MARK: Toolbar

            stop = self.stopButtonItem,
            close = self.closeButtonItem,
            safari = self.safariButtonItem else { return }

        let flexSpace = UIBarButtonItem(barButtonSystemItem: .FlexibleSpace, target: nil, action: nil)
        let refreshOrStopItem = webView.loading ? stop : refresh
        toolBar.setItems([close, flexSpace, back, flexSpace, refreshOrStopItem, flexSpace, forward, flexSpace, safari], animated: true)
    }

    // MARK: Actions
