There is a `sort` and a `limit` parameters so you might be able to work with these if it happens that the comment is in a specified place, but that's really hacky. Otherwise, I could think about adding filters such as:

    <comment-box hackernews="11850599" filter="id:3243534" class="border"></comment-box>

However arguably this is useful because you can show N comments and the UI is made around that.

You could also just hide everything else through CSS though:

https://jsfiddle.net/franciscop/fygps59v/2/

    comment-box .comment,
    comment-box .add {
      display: none;
    }

    comment-box #id-12898146 {
      display: block;
    }