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Click on your profile icon in top right corner
Click on 'Mailboxes'
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Managing Inboxes
Now that you can see Mailbox settings:
Click on the grey wording 'Manage'
You can mass-elect users and change access
You can individually set access to either full or read-only
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User Management
You can access users' management tab from workspace settings:
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Just make sure to click on 'Update' at the bottom for changes to take place.
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