Email Activity VIEW does not show the recipient, cc or bcc email addresses that the email was sent to

If you view the 'activity record' recorded when an Email is sent - the recipient contact name is shown, but you can't tell which email address the mail was sent to (and contacts may have multiple email addresses). In addition, if email was also CC'd or BCC'd - there's no indication of that when viewing the activity (civicrm/activity/view?atype=3&action=view...)

This is an audit trail problem, especially for Case-related emails (reported by Dave D) - so we should fix it.

This will require a schema change to fix.