Apple has released a firmware update for the 25W MagSafe Charger that’s compatible with the iPhone 12 and later and the latest AirPods and Apple Watch models.
Apple hasn’t offered any release notes, but the upgrade likely includes bug fixes and perhaps performance tweaks. There’s no obvious method for updating a MagSafe charger’s firmware, but it needs to be plugged in and connected to an Apple device for a firmware update to initiate. And you can check your MagSafe Charger’s firmware by following the instructions in MacRumor’s MagSafe Charger how to.
