Mozilla is giving up on their IRC server
As an admin helping out the Go Slack workspace, which is about to cross 39,500 registered users, they would be ill-advised to go with Slack if moderation is one of their goals. Full disclosure: our Workspakce does have some sort of agreement with Slack, so our space isn't a free space (we have full history), and even then we aren't able to get them to provide support around moderation of users.There is no mechanism to ignore a user, mute a user, or temporarily suspend a user if they need a timeout. The first two are completely impossible, while the latter today is manual / mostly possible using undocumented APIs and mechanizing of HTTP requests. Users reporting spam is done by them sending a message to an admin, or in the admin channel, and requires someone to manually intervene and moderate the message. So we effectively need to aim for follow-the-sun moderator coverage, which is a bit painful.In terms of usability and accessibility, some of the things Slack does (e.g., threads) are not super-inclusive or accessible to users who use screen readers. Today, based on feedback I've gotten, IRC is still superior for users who rely on screen readers due to some form of visual impairment.Whichever product they go with, it'd be nice if they provided an authenticated IRC gateway which would allow this class of user to have a better experience using the platform as they could use one of the text-based IRC clients that has served them well.For everyone who is saying they hope Slack isn't the choice, I'm fairly confident with these issues today they won't pursue Slack. If anyone from Mozilla, or any other org, would like to discuss some of the challenges we've had using Slack as an open community I'm more than happy to schedule time. I'd like to help you provide the best experience and community for your users.