- Added optional `--detect-local-mode` flag to kube-proxy. Valid values are "ClusterCIDR" (default matching previous behavior) and "NodeCIDR" ([#87748](https://github.com/kubernetes/kubernetes/pull/87748), [@satyasm](https://github.com/satyasm)) [SIG Cluster Lifecycle,...

- Expanded the on-disk kubelet credential provider configuration to allow an optional `tokenAttribute` field to be configured. When it is set, the kubelet will provision a token with the given audience bound to the current pod and its service account. This KSA token along with required annotations on the KSA defined in configuration...

- EmptyDir memory backed volumes are sized as the minimum of pod allocatable memory on a host and an optional explicit user provided value. ([#100319](https://github.com/kubernetes/kubernetes/pull/100319), [@derekwaynecarr](https://github.com/derekwaynecarr)) [SIG Node]

- Property `conditions` in `apiextensions.v1beta1.CustomResourceDefinitionStatus` and `apiextensions.v1.CustomResourceDefinitionStatus` is now optional instead of required. ([#64996](https://github.com/kubernetes/kubernetes/pull/64996), [@roycaihw](https://github.com/roycaihw))

Kubeadm: Automate certificate copy between control planes in HA setups

- Joining control plane nodes to a HA cluster can now be simplified by enabling the optional automatic copy of certificates from an existing control plane node.
- You can now use `kubeadm init --experimental-upload-certs` and `kubeadm join --experimental-control-plane --certificate-key`.

- Changed kuberc configuration schema. Two new optional fields added to kuberc configuration, `credPluginPolicy` and `credPluginAllowlist`. This is documented in [KEP-3104](https://github.com/kubernetes/enhancements/blob/master/keps/sig-cli/3104-introduce-kuberc/README.md#allowlist-design-details) and...

- The name of CEL(Common Expression Language) optional type has been changed from `optional` to `optional_type`. ([#124328](https://github.com/kubernetes/kubernetes/pull/124328), [@jiahuif](https://github.com/jiahuif)) [SIG API Machinery, Architecture, Auth, CLI, Cloud Provider, Network and Node]

- Adds support for `InterfaceNamePrefix` and `BridgeInterface` as arguments to `--detect-local-mode` option and also introduces a new optional `--pod-interface-name-prefix` and `--pod-bridge-interface` flags to kube-proxy. ([#95400](https://github.com/kubernetes/kubernetes/pull/95400), [@tssurya](https://github.com/tssurya))

* OpenStack cloud provider supports Cinder v3 API. ([#52910](https://github.com/kubernetes/kubernetes/pull/52910), [@FengyunPan](https://github.com/FengyunPan))
* kube-up: Add optional addon CoreDNS.  ([#55728](https://github.com/kubernetes/kubernetes/pull/55728), [@rajansandeep](https://github.com/rajansandeep))
    * Install CoreDNS instead of kube-dns by setting CLUSTER_DNS_CORE_DNS value to 'true'.

- Use omitempty for optional Job Pod Failure Policy fields ([#126046](https://github.com/kubernetes/kubernetes/pull/126046), [@mimowo](https://github.com/mimowo)) [SIG Apps]

### Bug or Regression