Disqus offers the best add-on tools for site owners to power discussions, increase engagement, and earn revenue.
Commento is a popular, fast, bloat-free commenting system that you can embed on your blog, news articles, and more. Open source at its core, Commento guarantees you privacy and does not include third-party trackers and advertisements, unlike alternatives such as Disqus.
Many websites contain secret messages and comments. Imagine you could make these messages visible or even add your own. Now imagine that this function would exist everywhere and only the users themselves would have control over it. Wouldn't that be great?Discontinued
The last update is from January 2018, and the Chrome extension is gone.
ommentics is a free, advanced PHP comment script with many features. Professionally written and with open source code, its main aims are to be integrable, customizable and secure. It is designed to be integrated into existing pages.