title: Why is UIWebView canGoBack=NO in iOS7?
body: <p>I'm embedding this web site into my app like this: </p>
  
  <pre><code>NSString *url = [NSString stringWithFormat:@"https://mobile.twitter.com/search?q=%@", @"@test OR #test"];
  url = [url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  [self.twitterWebView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:url]]];
  
  self.twitterWebView.scalesPageToFit = YES;
  </code></pre>
  
  <p>And I have 2 buttons for going back and forward in this web site. I'm calling </p>
  
  <p><code>[self.twitterWebView goBack];</code> and<br>
  <code>[self.twitterWebView goForward];</code> accordingly.</p>
  
  <p>This works fine on iOS 6 but on iOS 7, my web view's canGoBack and canGoForward properties are NO and thus my back and forward buttons do not work. </p>
  
  <p>As a side note, when the app is installed the first time, and the page is loaded the first time, my buttons work. But when I run my app again, and when I tap on a link on the web site, my web view's canGoBack property begins returning always NO. </p>
  
  <p>How can I solve this?</p>
  
  <p><strong>EDIT</strong>: I uploaded a mini test app that demonstrates my problem. You can download it from <a href="https://www.dropbox.com/s/a11os3z34g9ji6y/WebViewTest.zip" rel="noreferrer">here</a>. Please run the app on an iOS 7 simulator, see that the back button is working on the first installation of the app. Then quit, run the app again and you'll see that it'll stop working. </p>
  
  <p>By the way the problem seems to be about the twitter mobile site. You can try another web site address and see that.</p>