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If someone asks you for help in a direct message, you should point them to an appropriate public channel, and then help them there if you want.  It isn't impolite to ask that discussions be public.  The Open edX community is built on sharing, and sharing our help is important.  We have limited resources.  Help should be public so that others can learn, or help.  Even months later, public discussions can be found by searching Slack.  Direct messages are locked away.  Avoid them.

Use Threads

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In public channels, it can be hard to have a long conversation.  It's easy to feel like you are cluttering the channel with a discussion that most people don't want to see.  Slack's Thread feature is the best way to keep the discussion public, but out of everyone's way.  A thread is a regular discussion, but off to the side, so it's out of the main flow of the channel.

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