title: What is a "problem matcher" in compound tasks?
body: <p>The <a href="https://code.visualstudio.com/docs/editor/tasks#_compound-tasks" rel="nofollow noreferrer">documentation for compound tasks</a> states that for compound tasks that have a <code>dependsOn</code> entry,</p>
  <blockquote>
  <p>(...) Any background/watch tasks used in <code>dependsOn</code> with <code>&quot;dependsOrder&quot;: &quot;sequence&quot;</code> must have a problem matcher that tracks when they are &quot;done&quot;.</p>
  </blockquote>
  <p>What does this mean, exactly?</p>
  <p>The example does not mention this &quot;problem matcher&quot; and I tried to make a sequence of tasks running in a <code>shell</code> mode without such &quot;problem matches&quot; and they ran sequentially as expected.</p>