Unfortunately Slack still don’t support custom slash commands in threads, so we’re stuck with performing the slash commands in the context of the main channel 
The main problem we have with implementing thread support with a UI is obtaining human-readable names for each of the threads in the channel. If the thread starts more than 500 messages in the past, there is no way to get a sensible name without an additional HTTP request.
Judging by their API page, it looks like Slack have started implementing fairly strict rate limits for third parties. If we’re making many HTTP requests to fetch thread titles, then we’re going to hit the 50 req/min limit pretty quickly.
However, we could do something like this pretty easily:
/discourse post thread https://<slackname>.slack.com/archives/C6029G78F/p1522952993000017
(the URL is the slack thread URL)
We could skip the ‘start/end message’ UI, and just put the whole thread in the transcript.
The obvious problem is that it’s quite ninja, and not particularly pretty. What do you think @mcwumbly, do you think it would still be useful?
Can we stop blocking the word thr3ad yet? I just had to edit 8 legitimate occurrences in this post! 