- 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), [@...

* Update kube-dns to Version 1.14.8 that includes only small changes to how Prometheus metrics are collected. ([#57918](https://github.com/kubernetes/kubernetes/pull/57918), [@rramkumar1](https://github.com/rramkumar1))

does not support protobuf encoding, if you roll back to 1.5 after upgrading to
protobuf you will be forced to restore from backup, and you will lose any changes
since you converted to protobuf.  After conversion to protobuf, you should
validate the correct operation of your cluster thoroughly before returning it
to normal operation.

- Existing PVs are converted to use volume topology if migration is enabled. ([#83394](https://github.com/kubernetes/kubernetes/pull/83394), [@bertinatto](https://github.com/bertinatto))

   * awkward. This method lets you get a plain-old-{@code Map} out of a {@code Properties}.
   *
   * @param properties a {@code Properties} object to be converted
   * @return an immutable map containing all the entries in {@code properties}
   * @throws ClassCastException if any key in {@code properties} is not a {@code String}

   * awkward. This method lets you get a plain-old-{@code Map} out of a {@code Properties}.
   *
   * @param properties a {@code Properties} object to be converted
   * @return an immutable map containing all the entries in {@code properties}
   * @throws ClassCastException if any key in {@code properties} is not a {@code String}

### Increase the Kubernetes support window to one year

As of Kubernetes 1.19, bugfix support via patch releases for a Kubernetes minor release has increased from 9 months to 1 year.

A survey conducted in early 2019 by the working group (WG) Long Term Support (LTS) showed that a significant subset of Kubernetes end-users fail to upgrade within the previous 9-month support period. 

- The `EndpointSlice` API is now GA. The `EndpointSlice` topology field has been removed from the GA API and will be replaced by a new per Endpoint Zone field. If the topology field was previously used, it will be converted into an annotation in the v1 Resource. The `discovery.k8s.io/v1alpha1` API is removed. ([#99662](https://github.com/kubernetes/kubernetes/pull/99662), [@swetharepakula](https://github.com/swetharepakula))

- Because of the implementation logic of `time.Format` in golang, the displayed time zone is not consistent. ([#102366](https://github.com/kubernetes/kubernetes/pull/102366), [@cndoit18](https://github.com/cndoit18))
- Corrected the documentation for escaping dollar signs in a container's env, command and args property. ([#101916](https://github.com/kubernetes/kubernetes/pull/101916), [@MartinKanters](https://github.com/MartinKanters)) [SIG Apps]

* Modifying the default container GC policy parameters ([#27881](https://github.com/kubernetes/kubernetes/pull/27881), [@ronnielai](https://github.com/ronnielai))
* Kubelet can retrieve host IP even when apiserver has not been contacted ([#27508](https://github.com/kubernetes/kubernetes/pull/27508), [@aaronlevy](https://github.com/aaronlevy))