wpDiscuz User and Comment Mentioning allows to mention certain comments and users in comment text using #comment-id and @username tags. It comes with User Search bar, so you can find and tag any user/guest very easy. It also displays #ID of each comment to let you tag them. All mentioned users and comment authors will be notified via email. This addon replace @author and #comment-id to links with avatars. It opens a pop-up window with user and comment information when you hover on @author and #comment-id links. Please note, that the Comment Rich Editor must be enabled for this addon.
v7.1.1