wp-includes/PHPMailer/PHPMailer.php:5574Get the OAuthTokenProvider instance.
PHPMailer\PHPMailer\OAuthTokenProvider public function getOAuth() { return $this->oauth; }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/PHPMailer/PHPMailer.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.