- For Dynamic Resource Allocation, the new "v1beta1" kubelet gPRC was renamed so that the protobuf package name is unique. ([#128764](https://github.com/kubernetes/kubernetes/pull/128764), [@pohly](https://github.com/pohly)) [SIG Node and Testing]

* GCE: Fixes ILB sync on legacy networks and auto networks with unique subnet names ([#53410](https://github.com/kubernetes/kubernetes/pull/53410), [@nicksardo](https://github.com/nicksardo))

ontext","leadingRelative","implicitRelative","matchContext","matchAnyContext","elementMatchers","setMatchers","bySet","byElement","superMatcher","outermost","matchedCount","setMatched","contextBackup","dirrunsUnique","token","compiled","filters","unique","getText","isXML","selectors","until","truncate","is","siblings","n","rneedsContext","rsingleTag","winnow","qualifier","self","rootjQuery","parseHTML","ready","rparentsprev","guaranteedUnique","children","contents","prev","sibling","cur","target...

  - `admissionReviewVersions` default value is removed and the field made required for v1 (supported versions for AdmissionReview are `v1` and `v1beta1`)
  - The `name` field for specified webhooks must be unique for `MutatingWebhookConfiguration` and `ValidatingWebhookConfiguration` objects created via `admissionregistration.k8s.io/v1`

- In the course of admitting a single request, the ValidatingAdmissionPolicy plugin will perform no more than one authorization check per unique authorizer expression. All evaluations of identical authorizer expressions will produce the same decision. ([#116443](https://github.com/kubernetes/kubernetes/pull/116443), [@benluddy](https://github.com/benluddy)) [SIG API Machinery and Testing]...

  * Strategic Merge Patch

    * Reference docs now display the patch type and patch merge key used by `kubectl apply` to merge and identify unique elements in arrays.

      * `kubectl edit` and `kubectl apply` will keep the ordering of elements in merged lists ([#45980](https://github.com/kubernetes/kubernetes/pull/45980), [@mengqiy](https://github.com/mengqiy))

* Fix metrics API group name in audit configuration ([#53493](https://github.com/kubernetes/kubernetes/pull/53493), [@piosz](https://github.com/piosz))
* GCE: Fixes ILB sync on legacy networks and auto networks with unique subnet names ([#53410](https://github.com/kubernetes/kubernetes/pull/53410), [@nicksardo](https://github.com/nicksardo))

* kubelet: resolved hang/timeout issues when running large numbers of pods with unique configmap/secret references ([#74755](https://github.com/kubernetes/kubernetes/pull/74755), [@liggitt](https://github.com/liggitt))

- The calculation of pod UIDs for static pods has changed to ensure each static pod gets a unique value - this will cause all static pod containers to be recreated/restarted if an in-place kubelet upgrade from 1.20 to 1.21 is performed. Note that draining pods before upgrading the kubelet across minor versions is the supported upgrade path. (...

- CustomResourceDefinition schemas that use `x-kubernetes-list-map-keys` to specify properties that uniquely identify list items must make those properties required or have a default value, to ensure those properties are present for all list items. See https://kubernetes.io/docs/reference/using-api/api-concepts/#merge-strategy for details. ([#88076](ht...