It is soooooooooooooooooo intuitive
First you need to select account settings, account settings
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Then you select Change
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Then you select Advanced settings (maybe “more settings…”)
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Then you go to “Advanced” and “Add” and add the shared mailbox
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Bloopers?
Why do I need to go to “my account” settings when I just want to add a shared mailbox?
Then why should I need to select “change” for something I want to add?
…