Comment displays is part of the Display Suite and is an implementation of its API. It makes it possible to render the comment fields into regions.
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Updating to the 6.x-2.x branch
6.x-2.0 is a small update which brinds Comment Displays in line with the release numbering and UI changes for Display Suite 2.x.
Note: 6.x-2.1 removes an extra div from the comment template. This may affect your styling and page layouts, as this div made some comments fall outside the #comments block.
The Drupal 7 version of Comment displays has been merged into the Drupal 7 version of Display Suite.