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Bots continue to function the same as usual, namely bots can be configured to use either the member or system admin. If a bot is configured to be a member the bot could have its touse_channel_mentions and create_post permissions restricted on specific channels. However, to lose the create_post permission the bot would also have to have post:all and post:channels disabled also.
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Relationship between a channel scheme and its higher-scoped scheme
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