title: Can't make dump() work in Symfony 4.2 toolbar
body: <p>I am new to Stack Overflow and programming and I have a bad english, so sorry in advance if I don't ask things correctly.</p>
  <p>I am learning how to use Symfony and I can't get the dump() function to work properly. I followed the instruction at :
  <a href="https://symfony.com/doc/current/components/var_dumper.html" rel="nofollow noreferrer">https://symfony.com/doc/current/components/var_dumper.html</a></p>
  <p>I installed the VarDumper component and the Debug Bundle using composer :</p>
  <pre><code>composer require --dev symfony/debug-bundle
  composer require --dev symfony/var-dumper
  </code></pre>
  <p>Then I used dump() in my app controller in order to show the HTTP request when I submit a form :</p>
  <pre><code>use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
  use Symfony\Component\HttpFoundation\Response;
  use Symfony\Component\Routing\Annotation\Route;
  use Symfony\Component\HttpFoundation\Request;
  
   class BlogController extends AbstractController
  {
      /**
       * @Route(&quot;/blog/new&quot;, name=&quot;blog_create&quot;)
       */
      public function blog_create(Request $request): Response
      {
          dump($request);
          return $this-&gt;render('blog/create.html.twig',['request'=&gt;$request]);
      }
  }
  </code></pre>
  <p>The dump() should appear in the debug tool bar. Instead, when I call 'blog/new', I just have the normal display of the form page and my debug toolbar doesn't show. However, I know that the VarDumper component works because I tried to use the dump server and the console shows me the result of the dump each time I call 'blog/new'. I am able to find the content of my form in this dump.</p>
  <p>Does someone have an idea on how to show the result of dump() inside the debug toolbar and without breaking it ?</p>
  <p>Regards,</p>
  <p>myst</p>