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Once a team is shared, it automatically appears as a public team for people to join (even if it is private on the originating organisation).
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Channel Sharing per team
Once a user has added a team, all channels are shared by default, but they can change that by
Clicking the channels shared item on their row.
Going to Edit > Channels shared
Once they do that, a modal pops up, allowing them to decide which channels to share.
They can share all channels
Channels except the selected channels
Specific channels
For both 2 and 3, the input box will be a search autocomplete, allowing users to search and select channels.
The limit of channels that can be selected is unlimited.
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Once done, the user can click on Save to create a connection. They get a share popup to share the code needed to accept the connection.
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