I think https://slackline.io/ https://slackline.io/ is really interesting, channels shared between different team. I see the use case for this, in GitLab issues

I think https://slackline.io/ https://slackline.io/ is really interesting, channels shared between different team. I see the use case for this, in GitLab issues it is also annoying that it is hard to work with people from outside the company if the issue is private. But there are no plans to do something like this at this moment. However, it is all open source, feel free to add functions. And because you don't have to pay for accounts there is no limit to the number of people that can join.