HubZilla

Hubzilla (formerly RedMatrix) is an open source, federated, community web server that started as a fork of Friendica.

Selfdogfooding

Mike Macgirvin: founder of friendica [1] and a maintainer of HubZilla
- his HubZilla profile: https://macgirvin.com/channel/mike

As of 2016-06-21, the development branch has microformats2 h-cards that seem to have been copied from a Friendica Pull Request. HubZilla Commit
As of 2016-06-23, the development branch has microformats2 h-entries marked up PR
As of 2017-02-15, an experimental module is available for sending webmentions https://github.com/redmatrix/hubzilla-addons/tree/dev/webmention
As of 2017-10-22, Bridgy Fed federates IndieWeb replies, likes, and reposts to and from HubZilla via webmention/OStatus.

Comments, while having their own URL, render nearly identical output html. Thus comment URLs currently have the original post of a thread as the h-entry, not the comment.
Comments canonical URL are also not on the author's domain, thus could be forged (for microformats consumers)
Requested Webmention support following W3C REC status, Currently hooks have been added to allow a cron to handle sending webmentions in a plugin. Feature Request Thread
Very confusing UI / UX. Initial creation of an account asks you to name a channel (you never name your account). You can create multiple channels as well. Finding how to post to the channel is non-obvious. To delete your account you must delete your channel.