I've spent a lot of time thinking about the problem of how to make threading work as the lead developer of Zulip, an open source group chat application where every conversation is threaded, and I think adding Facebook-style comment threads to messages is the wrong approach.<p>Fundamentally, what you want is to be able to read and participate in multiple conversations with a given group of people (a channel) at the same time, with as little overhead as possible, and when catching up later, you want to be able to read one conversation at a time, not all of them mixed together. And you don't want to have to go into some special mode to do so; you want it to feel like the default thing to do. I don't expect this to get a lot of use. The data Slack mentioned to the press shows that even Slack employees hardly use the feature; from <a href="http://www.theverge.com/2017/1/18/14305528/slack-threads-threaded-messages" rel="nofollow">http://www.theverge.com/2017/1/18/14305528/slack-threads-thr...</a>:<p>> "But employees at Slack, who have been testing threads for months, say they are meant to complement public channels — not replace them. Joshua Goldenberg, the company's head of design, told me that only 7 or 8 percent of his time in Slack has moved to threads."<p>If the people at Slack's who designed this feature hardly use it, I doubt it's going to solve the big problems with Slack/Hipchat/Campfire/IRC, namely that their chat room model doesn't work once a channel gets beyond a few dozen actually active participants.<p>If you're interested in a good solution to this problem, check out how Zulip does threading (<a href="https://zulip.org" rel="nofollow">https://zulip.org</a> has some screenshots (of an old visual design, sadly), or visit the developer community at <a href="https://chat.zulip.org" rel="nofollow">https://chat.zulip.org</a> to see it in action). Zulip's threading is the main reason why it's become the open source group chat application project with the most active development community (see e.g. <a href="https://github.com/zulip/zulip/graphs/contributors" rel="nofollow">https://github.com/zulip/zulip/graphs/contributors</a>).<p>(Edited for clarity)