title: Show welcome message for successful login (after redirect)?
body: <p>I have a modal login page which users can log in with ajax (created with vue Js) : </p>
  
  <pre><code>return login_modal.$http.post('/login', data).then(
      function (response) {
          if (response.data.auth) {
              window.location = response.data.intended_url
          } else {
              login_modal.incorrect_credential = true;
          }
      }
  )
  </code></pre>
  
  <p>When user login successfully, the page is redirected to the firstly requested page OR home page. All things works great </p>
  
  <p>Now I want to show an alert or a toastr message to user after he/she is redirected, but I don't know if he/she is just logged in or logged in before!  The welcome message should be show only if user is just logged in! one time only. </p>
  
  <p>I know how to use cookies or sessions in php or js, but I don't know how to accomplish this! for example saving a short living cookie (5 seconds!!). Is this the right way?</p>