title: Kibana - missing text highlighting for multi-field mapping
body: <p>I am experimenting with ECS - Elastic Common Schema.
  We need to highlight text search for the field error.stack_trace . This field is a multi-field mapped defined <a href="https://www.elastic.co/guide/en/ecs/current/ecs-error.html#field-error-stack-trace" rel="nofollow noreferrer">here</a></p>
  <p>I just did a simple test running Elasticsearch and Kibana 7.17.4 one field defined as multi-field and one with single field.</p>
  <pre><code>PUT simple-index-01
  {
      &quot;mappings&quot;: {
        &quot;properties&quot;: {
          &quot;stack_trace01&quot;: { &quot;type&quot;: &quot;text&quot; },
              &quot;stack_trace02&quot;: {
                &quot;fields&quot;: {
                  &quot;text&quot;: {
                    &quot;type&quot;: &quot;text&quot;
                  }
                },
                &quot;type&quot;: &quot;wildcard&quot;
              }
            }
          }
  }
  
  POST simple-index-01/_doc 
  { 
    &quot;@timestamp&quot; : &quot;2022-06-07T08:21:05.000Z&quot;, 
    &quot;stack_trace01&quot;: &quot;java.lang.NullPointerException: null&quot;,
    &quot;stack_trace02&quot;: &quot;java.lang.NullPointerException: null&quot;
  }
  </code></pre>
  <p><a href="https://i.stack.imgur.com/gMJQX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gMJQX.png" alt="enter image description here" /></a></p>
  <p>Is it a Kibana expected behavior not to highlight multi-fields?</p>