Merged requested to merge erciccione/monero-site:hangouts-slack into master
Slack is not open source friendly: its code is closed source, to join people need an "invitation" and PMs between users can be read by the administrators.
Beside all that, nobody really use it. Most of the people prefer Riot or MatterMost. I think would be better to remove it and substitute it with Weblate, the new platform for translations.