- Supported `BackoffLimitPerIndex` in Jobs. ([#118009](https://github.com/kubernetes/kubernetes/pull/118009), [@mimowo](https://github.com/mimowo))
- The `IPTablesOwnershipCleanup` feature (KEP-3178) is now GA; kubelet no longer
  creates the `KUBE-MARK-DROP` chain (which has been unused for several releases)

- Added a condition `NonStructuralSchema` to `CustomResourceDefinition` listing Structural Schema violations as defined in the [KEP](https://github.com/kubernetes/enhancements/blob/master/keps/sig-api-machinery/20190425-structural-openapi.md). CRD authors should update their validation schemas to be structural in order to participate in future CRD features. ([#77207](https://gi...

- Introduced `v1alpha1` API for validating admission policies, enabling extensible admission control via CEL expressions (KEP  3488: CEL for Admission Control). To use, enable the `ValidatingAdmissionPolicy` feature gate and the `admissionregistration.k8s.io/v1alpha1` API via `--runtime-config`. ([#113314](https://github.com/kubernetes/kubernetes/pull/113314), [@cici37](h...

- Remove `tolerate-unready-endpoints` annotation in Service deprecated from 1.11, use `Service.spec.publishNotReadyAddresses` instead....

`ApplySets`. An `ApplySet` is a server-side object (by default, a Secret; ConfigMaps are also allowed) that kubectl can use to accurately and efficiently track set membership across `apply` operations. The format used for `ApplySet` is set out in  [KEP 3659](https://github.com/kubernetes/enhancements/issues/3659) as a low-level specification.  Other tools in the ecosystem can also build on this specification for improved interoperability.  To try the ApplySet-based pruning alpha, set `KUBECTL_APPLYSET=true`...

  
  See here for guidance on getting permanent links to files: https://help.github.com/en/articles/getting-permanent-links-to-files
  
  Please use the following format for linking documentation:
  - [KEP]: <link>
  - [Usage]: <link>
  - [Other doc]: <link>
  --> (#104782, @kerthcet) [SIG Scheduling and Testing]

- Alpha swap support can now be enabled on Kubernetes nodes with the `NodeSwapEnabled` feature flag. See [KEP-2400](https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/2400-node-swap/README.md#design-details) for details. ([#102823](https://github.com/kubernetes/kubernetes/pull/102823), [@ehashman](https://github.com/ehashman))

PodReady++ feature now has `kubectl` CLI support.

Progress was made towards finalizing the IPv6 dual stack support KEP and support for topological routing of services.

### SIG Node

- Added alpha support for user namespaces in pods phase 1 (KEP 127, feature gate: UserNamespacesStatelessPodsSupport) ([#111090](https://github.com/kubernetes/kubernetes/pull/111090), [@rata](https://github.com/rata))

- Added pod version skew strategy for seccomp profile to synchronize the deprecated annotations with the new API Server fields. Please see the corresponding section [in the KEP](https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/135-seccomp/README.md#version-skew-strategy) for more detailed explanations. ([#91408](https://github.com/kubernetes/kubernetes/pull/91408), [@saschagrunert](https://github.com/saschagrunert))...