WordPressMailNames
Corex\Mail\Capture\WordPressMailNames · class · Core layer
Names the emails WordPress builds itself, for the Email Studio log: each is made by a filter WordPress runs just before it calls wp_mail(), so the filter leaves the name for that email (spec 113, research R4). The filters’ values pass through unchanged. The comment emails are not named: WordPress builds their text once and then mails each recipient, so a name left for the first would be wrong for the rest. They are “Other: wp_mail”.