Apple has rolled out a new firmware update for AirPods 4, likely focusing on bug fixes and other improvements.
AirPods 4th-generation
Apple continues to update firmware for the AirPods lineup, with the AirPods 4 being the latest to receive an update.
As 9to5Mac points out, the update build number is 7B19, the same as last week's update for the AirPods Pro 2. However, the AirPods 4 will not see the new Hearing Test, Hearing Protection, and Hearing Aid features exclusive to the AirPods Pro 2.
This means that the AirPods 2 likely received bug fixes and performance improvements. As of now, there are no release notes for the update.
AirPods firmware updates are installed automatically when the AirPods are inside the charging case and connected to an iOS device. There is no manual installation method for this firmware update.