Apple Mail To/CC/BCC field (+) not populating email address from iCloud Contacts

Just setup a new iMac (Monterey) and am having a minor issue with Mail. The little blue plus shortcut to add email addresses to the To/CC/BCC does not work.

Clicking on the plus brings up the full iCloud contact list without a problem, but clicking on a specific email address does not populate the field. It just does nothing.

If I start typing the email address in the To/CC/BCC filed it suggests the address from the contacts without a problem. This requires a two step process to look up the address and then type it in.

Is there a way to get the (+) shortcut to work?