anchor.diff:  }
   ```
   
  -If `ProviderSignInUtils.getConnection()` returns a connection, that means there was a failed provider sign in attempt that can be completed if the user registers to the application. 
  +If `ProviderSignInUtils#getConnection()` returns a connection, that means there was a failed provider sign in attempt that can be completed if the user registers to the application. 
   In that case, a `SignupForm` object is created from the user profile data obtained from the connection's `fetchUserProfile()` method. 
   Within `fromProviderUser()`, the `SignupForm` properties may be set like this:
   
  
positive.code:     Account account = createAccount(form, formBinding);
      if (account != null) {
          SignInUtils.signin(account.getUsername());
          ProviderSignInUtils.handlePostSignUp(account.getUsername(), request);
          return "redirect:/";
      }
      return null;
  
negative.code: Twitter, for example, does not provide a user's email address, so the `getEmail()` method will always return null after a sign in attempt with Twitter.
  
  After the user has successfully signed up in your application a connection can be created between the new local user account and their provider account. 
  To complete the connection call `ProviderSignInUtils#doPostSignUp()`. 
  For example, the following method handles the sign up form submission, creates an account and then calls `ProviderSignInUtils#doPostSignUp()` to complete the connection:
  
  ```java
  @RequestMapping(value="/signup", method=RequestMethod.POST)
  