### Other notable changes

which have no other owners are deleted from the live object, or reset to their default value if they have one. Safe ownership transfers, such as the transfer of a `replicas` field from a user to an HPA without resetting to the default value are documented in [Transferring Ownership](https://kubernetes.io/docs/reference/using-api/api-concepts/#transferring-ownership) ([#92661](https://github.com/kubernetes/kubernetes/pull/92661), [@jpbetz](https://github.com/jpbetz)) [SIG API Machinery, CLI, Cloud...

- Protobuf serialization of metav1.MicroTime timestamps (used in `Lease` and `Event` API objects) has been corrected to truncate to microsecond precision, to match the documented behavior and JSON/YAML serialization. Any existing persisted data is truncated to microsecond when read from etcd. ([#111936](https://github.com/kubernetes/kubernetes/pull/111936), [@haoruan](https://github.com/haoruan)) [SIG API Machinery]

* Pod affinity `nodeSelectorTerm.matchExpressions` may now be empty, and works as previously documented: nil or empty `matchExpressions` matches no objects in scheduler. ([#62448](https://github.com/kubernetes/kubernetes/pull/62448), [@k82cn](https://github.com/k82cn))