Within Teamwork Chat, you can choose to
automatically add new users to a
particular channel by default.
To make an existing
conversation/channel into a default
channel, click the options button (three dots) in the top right of the channel and select Edit channel.
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In a conversation, you will need to convert
it to a channel first by clicking Convert
to channel.
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In the create/edit modal, select the Automatically add new users to this
channel option.
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Once selected, every new member will be added
to this channel as default.
Note: Only a public channel
can be set as a default channel.