The Trisquel forum has served for several years already, using some Drupal
forum module. However, it has many issues:
It is not responsive, meaning you can't read posts well on a smartphone or
a tablet (unless you are constantly zooming, and trying to touch small
buttons).
Only some HTML can be used for post formatting, not Markdown or even
BBCode.
There could be better moderation tools (as well as more moderators...).
It is "non-standard" in the sense that most people are not used to a forum
that is embedded within Drupal.
It could look better, more readable (some texts are quite small), and with
a less distracting background.
I personally would recommend those free forum software: Flarum (PHP,
MIT/Expat), Discourse (Ruby, GPLv2), NodeBB (Node.js, GPLv3). Such forum
software would probably be hosted on a subdomain.
I know you guys are very attached to mailing lists, so I'll warn you already
that those forum software are not intended to be used with e-mail. Generally,
you can only reply through a Web browser.
There probably is no importer script for Drupal forums either, so the old
forums will have to be accessible from somewhere.
Eventually, maybe redesign the whole site to look more modern and responsive.
We could take inspiration from Antergos and Fedora.
