How to do this [4.2.2]

[MarkFL]

In your "additional.css" template add the following class:

.postcontainerOP {
	border-right: 3px solid red !important;
	border-left: 3px solid red !important;
}

In your "postbit_legacy" template, near the top, locate the code:

<li class="postbitlegacy postbitim postcontainer {vb:raw post.statusicon}" id="post_{vb:raw post.postid}">

And replace it with this:

<li class='postbitlegacy postbitim postcontainer {vb:raw post.statusicon}<vb:if condition="$thread['postuserid'] == $post['userid']"> postcontainerOP</vb:if>' id="post_{vb:raw post.postid}">