No, it saves outgoing addresses in the collected address book. ie People you have sent mail to.

Open Preferences from the menu search collect Change the preference to not save them if that is what you want.

When I prepare an email to someone and start typing their name in the To box, for one recipient, it shows two addresses, one of which is obsolete. The bad address is NOT in collected addresses, nor in my address book. How do I get rid of it?

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