CSS - User posts divider line

[awesomerobot (Kris)]

The border between posts is on two divs, .topic-avatar and .topic-body this would remove the border:

.topic-avatar, 
.topic-body {
  border-top: none;
}

You may also want to remove borders from the small topic actions like this:

you’d accomplish that with

.small-action {
  border-top: none;
}