The basic problem with Slack is that it's not libre. It's a fine product in many other ways. I won't defend the ethics of libre: I'll leave that up to rms, who

The basic problem with Slack is that it's not libre. It's a fine product in many other ways. I won't defend the ethics of libre: I'll leave that up to rms, who has done a more-than-adequate job. But libre is a more ethical choice than proprietary.