Most "email testing" advice ends at stubbing the send call. You assert that your app tried to send a message, and the test goes green. That leaves the interesting half untested: whether the message actually left your infrastructure, whether the template rendered, and whether the six-digit code inside it matches the one your backend is willing to accept. This walks through the other approach — driving a real signup flow in Playwright , letting a real email get delivered to a real inbo...