title: Is a case insensitive aggregate match possible in Mongo without using $regex operators?
body: <p>I'm aware of how to use a case insensitive collation with <code>find()</code>, but is there something similar for aggregation?  The only case insensitive aggregation operators I've found so far use some variant of $regex, all of which ignore the index, as far as I can tell.  Perhaps I am missing something.</p>
  <p>I'm hoping for something similar to</p>
  <pre><code>[$match: {{name: &quot;Foo&quot;}, collation: {locale: 'en', strength: 2}}]
  </code></pre>
  <p>which would find name == &quot;foo&quot;, &quot;FOO&quot;, &quot;fOO&quot;, etc., but any mechanism to do it with an index would be welcome.</p>
  <p>Bonus if there's a Mongoose way to do so!</p>