title: HTTP error 400 accessing /github-webhook/. Hook should contain event type
body: <p>I call webhook Jenkins from Gitlab and get following error :</p>
  
  <pre><code>&lt;html&gt;
      &lt;head&gt;
          &lt;meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/&gt;
          &lt;title&gt;Error 400 Hook should contain event type&lt;/title&gt;
      &lt;/head&gt;
      &lt;body&gt;
          &lt;h2&gt;HTTP ERROR 400&lt;/h2&gt;
          &lt;p&gt;Problem accessing /github-webhook/. Reason:
  
              &lt;pre&gt;    Hook should contain event type&lt;/pre&gt;
          &lt;/p&gt;
          &lt;hr&gt;
          &lt;i&gt;
              &lt;small&gt;Powered by Jetty://&lt;/small&gt;
          &lt;/i&gt;
          &lt;hr/&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>What i have done? i read reference here but not working :</p>
  
  <p><a href="https://stackoverflow.com/questions/36609629/jenkins-github-plugin-returns-error-400-hook-should-contain-event-type">Jenkins github plugin returns error 400 &quot;Hook should contain event type&quot;</a></p>
  
  <p><strong>Why i ask again to similar title:</strong></p>
  
  <p>Cause the solution above still not working for me.</p>
  
  <p><strong>What i can sure :</strong></p>
  
  <p>I sure that Jenkins can connect to Gitlab, cause i can built project "X" manually and no error. My problem here when i want automatically build when i push to gitlab and i always get that error. Can anyone help me ?</p>