Libre opensource version of Slack?
@eilis I like Riot¹ which is a front-end for Matrix². I use it with students and it works great for our needs.
1. https://riot.im/2. https://matrix.org
@KnowPresent @eilis it's up in the air still. We've been trying RocketChat over at talk.lurk.org. Personally I am more in favor of federated alternatives based on xmpp (conversejs.org or movim.eu are good webclients).
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