Model
InvoiceNotifier
Magento\Sales\Model\Order\InvoiceNotifier
What it does
InvoiceNotifier is responsible for sending invoice notification emails to customers when an invoice is created or updated.
Developers use this class when they need to trigger invoice email notifications programmatically, such as after creating an invoice through custom code or integration.
It extends AbstractNotifier and utilizes InvoiceSender to handle the actual email delivery process.