https://arstechnica.com/gadgets/2021/10/airpods-pro-firmware-update-makes-finding-lost-earbuds-easier/

On Wednesday, Apple began updating all AirPods models (AirPods, AirPods Pro, and AirPods Max) to firmware 4A400. While the normal, non-Pro, non-Max AirPods don't appear to have gotten much from this update, AirPods Pro and AirPods Max got new "Find My" features, and AirPods Pro now support a feature called "Conversation Boost."