What third party services are there to add commenting functionality to a website?

Question

Web development

Hello everyone,
The question arose of adding the ability to comment on pages on the website. Now I would not like to waste time on the implementation of this functionality personally. I often saw built-in blocks with comments from third-party services on websites. I would like to ask what services for adding comments exist at this point in time? Of the requirements is the ability to use social. networks for authorization (facebook, vkontakte, possibly twitter), responsive support and the availability of free use with a certain limit (possibly paid, but at an affordable price).
Thanks a lot for your answers.

Answer 1

https://publishers.disqus.com/cackle.me
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