Disqus and GoatCounter extensions are available below.
You might be able to find more extensions by searching social media using #StaticUltra or Google. But at the time of writing I don't think anyone has shared any. As time goes by who knows? xD
Free analytics for your site. Find out which pages your visitors are viewing, where they're coming from, and much more!
Free comment system for your site. Once installed, make a thread by simply adding one small line of HTML to any of your pages!
Highlight the <code> blocks on your page. Great if you're writing tutorials or sharing code. Supports a ton of languages, including HTML, CSS, JS, C/C++, PHP, Python, Lua and many more.