This means your new MacBook won't blare out said startup chimes when it's opened up in public places or mid-meeting. According to Apple, the automatic start-up (as in, not from sleep mode), kicks in when you start up your MacBook Pro by opening it or plugging it in, when connecting it to power while the lid is open, and even when it's closed if you've connected the machine to an external display.

Pingie, which discovered the change in Apple's support notes, added it brings (at least part of) the MacBook series in line with the rest of the Apple product family: there's not startup noise on iPhones, iPads or the Apple Watch. And here's all those startup chimes, all in a row: