bring back chat

I've been on various internet sites my whole life and have seen a similar pattern. People love chatting and want immediate updates about new responses, but whenever a site grows large enough, it often has to scale back "always-refreshing" features because they're too demanding on server resources.
The server has to compute the names and numbers of new posts at all yours chats/groups, keeping the left chat list perfectly updated. This is hard.
Having to open Chat deliberately is less convenient, but it also requires less computation.

I suspect that's the issue here. Just a thought.