I had to document the display of the Comment Tab in the Administration interface (see EZP-22264)
And now in documentation, we have nothing up-to-date about commenting (on doc.ez.no and confluence.ez.no) : all the configuration doc is on github.com (https://github.com/ezsystems/CommentsBundle/blob/master/Resources/doc/index.md)

The purpose is to not duplicate the documentation, if possible, and to document this CommentBundle features, in accordance to other bundled features.

existing doc about the topic :http://doc.ez.no/eZ-Publish/User-manual/5.x/The-Administration-Interface/The-Object-Edit-Interface