You may want to consider Loomio.org.
Used by Podemos, the Pirate Party of Belgium, the government of Taiwan, and lots of other organizations. Translated into 35 languages.
It is both software, and a community.
They are not just discussion/chat, they also help groups “make better decisions together.”
Loomis grew out of the occupy movement, it is open source, maintained by a worker cooperative. They first rose to prominence in Taiwan, when the government used participative democracy to draft the law regulating Uber, taking into account all the different stake holders issues. I heard about them then. And now widely used in Taiwan’s government.
Here is professor Richard Wolff’s interview with the founder.
It starts at 29 25
Here is the Wikipedia article.
Here is the documentation.
I have not tried the software, but it all looks very reasonable to me.
All written in Ruby. I like that.
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