## Before Upgrading

* When Response is a `metav1.Status`, it is no longer copied into the audit.Event status. Only the "status", "reason" and "code" fields are set.  For example, when we run `kubectl get pods abc`, the API Server returns a status object:

- Graduated `PodObservedGenerationTracking` feature to beta and had it on by default. This feature meant that the top level `status.observedGeneration` and `status.conditions[].observedGeneration` fields in Pods were populated to reflect the `metadata.generation` of the podspec at the time that the status or condition was reported. ([#132912](https://github.com/kubernetes/kubernetes/pull/132912), [@natasha41575](https://github.com/natasha41575)) [SIG Apps, Node and...

- Kube-apiserver: fix a possible panic validating a custom resource whose CustomResourceDefinition indicates a status subresource exists, but which does not define a `status` property in the `openAPIV3Schema` ([#135362](https://github.com/kubernetes/kubernetes/pull/135362), [@fusida](https://github.com/fusida)) [SIG API Machinery]

- Kube-apiserver: Fixed a possible panic validating a custom resource whose `CustomResourceDefinition` indicates a status subresource exists, but which does not define a `status` property in the `openAPIV3Schema`. ([#133721](https://github.com/kubernetes/kubernetes/pull/133721), [@fusida](https://github.com/fusida)) [SIG API Machinery, Apps, Architecture, Auth, Autoscaling, CLI, Cloud Provider,...

    * If the serialization type is 'application/json':
    * If serialization fails, and the original status code was an failure (e.g. 4xx or 5xx), the original status code will be returned.

  - Added `allocatedResources` field to container status in pod status that describes the node resources allocated to a pod.
  - Added `resources` field to container status that reports actual resources applied to running containers.
  - Added `resize` field to pod status that describes the state of a requested pod resize.

### **Application Autoscaling**
#### Horizontal Pod Autoscaler
* [alpha] [HPA Status Conditions](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale-walkthrough/#appendix-horizontal-pod-autoscaler-status-conditions).


### **Cluster Lifecycle**
#### kubeadm

- Tighten validation on the qosClass field of pod status. This field is immutable but it would be populated with the old status by kube-apiserver if it is unset in the new status when updating this field via the status subsource. ([#127744](https://github.com/kubernetes/kubernetes/pull/127744), [@carlory](https://github.com/carlory)) [SIG Apps, Instrumentation, Node, Storage and Testing]...

- Pod Log stats for windows now reports metrics ([#99221](https://github.com/kubernetes/kubernetes/pull/99221), [@jsturtevant](https://github.com/jsturtevant)) [SIG Node, Storage, Testing and Windows]

- Added a `.status.features.supplementalGroupsPolicy` field to Nodes. The field is true when the feature is implemented in the CRI implementation (KEP-3619). ([#125470](https://github.com/kubernetes/kubernetes/pull/125470), [@everpeace](https://github.com/everpeace)) [SIG API Machinery, Apps, Node and Testing]