Easily add Private Messaging for your users to your WordPress site with Cartpauj PM (Private Messages).
Enables users to post questions and answers (Q&A) in a Stackoverflow style. Plugin includes social media login registration and can be customized
Embed a Bublaa Forum into your site and replace your comment system with Bublaa Comments (optional).
Add the new comment subscription option to the blog comment form.
Provides bbPress with support for topic thumbnails.
vBPress seamlessly integrates WordPress with vBulletin
Says Something Else replaces the default “SoAndSo says:” in WordPress comment threads with whatever you specify.
Moodlight allows your visitors to add their mood on posts via comments.
Allows the user to display statistics for their blog's/forum's Disqus comments.
YATCP allows you to have threaded comments (i.e. reply to existing comments) in your wordpress.
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