Apple has released the first updated firmware for the MagSafe Duo charger, which is compatible with both the Apple Watch and MagSafe-compatible iPhone models.
The new firmware is version 10M3063, but in the settings app, you'll see a version number of 256.1067.0, up from 22.214.171.124.
Since its release, the MagSafe Duo, which was first released in 2020 alongside the iPhone 12, hasn't received a firmware update. Apple has not provided release notes, so it's unclear what the new firmware will bring.
The MagSafe Duo's firmware is not required to be updated. It must be plugged into and connected to an Apple device for a firmware update.