title: Namespace/subdomain in Gitlab not working
body: <p>I am new on Gitlab. In several tutorials, I see domains like <code>myname.gitlab.io</code> or <code>myname.gitlab.com</code> as well <code>gitlab.com/myname</code>. But I only call <code>gitlab.com/myname</code>, the others throw a 404 error.</p>
  
  <p><strong>Do I have to activate the subdomains somehow?</strong></p>