title: How to make custom form-tag in contact form 7 required
body: <p>So i make custom form-tag in contact form 7! It is a drop down with list of my courses and now I want to make it required because that is the main thing in whole form. 
  So can someone give me a tip how to do that? </p>
  
  <p>When I do the <code>[myCustomField* course-name class:custom-field]</code></p>
  
  <p>It does not working with <b>*</b>
  So if someone can help it will be great! </p>