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Many of my contacts have multiple email addresses stored in Contacts.app. If I compose an email in Mail.app using a group as the recipient, then for every person in this group who has more than one address, it will pick one automatically. What logic is used to choose the address?
The same thing happens if I drag one of these contacts into Mail.app as a recipient. I know I can click on the recipient name and choose an address from the drop-down list, but I want to know how to set the default "priority" address.