title: ASP.NET authentication cookie not deleting after Firefox is closed
body: <p>Im developing a small web aplication, used in a shared computer.</p>
  
  <p>When the user closes the browser window, i want the session and the authentication to be deleted.</p>
  
  <p>In the Login page i use something like this to authenticate the user:</p>
  
  <pre><code>FormsAuthenticationTicket authTicket =
        new FormsAuthenticationTicket(1,txtUser.Text,
                                      DateTime.Now,
                                      DateTime.Now.AddMinutes(5),
                                      false,"");
  
  string encTicket = FormsAuthentication.Encrypt(authTicket);
  HttpCookie faCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encTicket);
  HttpContext.Current.Response.Cookies.Add(faCookie);
  string redirectUrl = FormsAuthentication.GetRedirectUrl(txtUser.Text, false);
  HttpContext.Current.Response.Redirect(redirectUrl);
  </code></pre>
  
  <p>As you can see, i have set the "isPersistent" variable to false.</p>
  
  <p>This seems to work on Chrome (haven't tested on IE), however, when i run the app on Firefox, with multiple tabs activated, if i close the browser and open again, im still authenticated, and the cookie is still there!</p>
  
  <p>Its really strange, beacause the cookie should be removed on closing... Is this a bug from Firefox, when you have multiple tabs opened? How can i fix this?</p>
  
  <p>Help is much appreciated!</p>
  
  <p>Thanks in advance</p>