Kubernetes was previously detecting that the image filesystem was split, even when that was not really the case ([#128344](https://github.com/kubernetes/kubernetes/pull/128344), [@kannon92](https://github.com/kannon92)) [SIG Node]

[beta] User-provided apiservers can be aggregated (served along with) the rest of the Kubernetes API. See [Extending the Kubernetes API with the aggregation layer](https://kubernetes.io/docs/concepts/api-extension/apiserver-aggregation/), [Configure the aggregation layer](https://kubernetes.io/docs/tasks/access-kubernetes-api/configure-aggregation-layer/), and [Setup an extension API server](https://kubernetes.io/docs/tasks/access-kubernetes-api/setup-extension-api-server/).

* [alpha] Adding...

    - [Certificates API](#certificates-api)
    - [Cluster Autoscaler](#cluster-autoscaler)
    - [Deployment](#deployment)
    - [Federation](#federation)
    - [Internal Storage Layer](#internal-storage-layer)
    - [Node Components](#node-components)
    - [kubectl](#kubectl)
    - [RBAC](#rbac)
    - [Scheduling](#scheduling)
    - [Service](#service)
    - [StatefulSet](#statefulset)

- Fixed a regression in default configurations, which enabled `PodDisruptionConditions`
  by default, that prevented the control plane's pod garbage collector from deleting
  pods that contained duplicated field keys (environmental variables with repeated keys or

- Kubeadm: the command "kubeadm token create" now has a "--certificate-key" flag that can be used for the formation of join commands for control-planes with automatic copy of certificates ([#84591](https://github.com/kubernetes/kubernetes/pull/84591), [@TheLastProject](https://github.com/TheLastProject))

### SIG Network

- Fixed a regression in default 1.26 configurations, which enabled PodDisruptionConditions by default, 

- The `KubeletSeparateDiskGC` feature gate is now beta. This split image filesystem feature enables kubelet to perform garbage collection of images (read-only layers) and/or containers (writeable layers) deployed on separate filesystems. gate is now beta. ([#126205](https://github.com/kubernetes/kubernetes/pull/126205), [@kwilczynski](https://github.com/kwilczynski))

- Add support for CEL expressions with escaped names in structured authentication config.  Using `[` for accessing claims or user data is preferred when names contain characters that would need to be escaped.  CEL optionals via `?` can be used in places where `has` cannot be used, i.e. `claims[?"kubernetes.io"]` or `user.extra[?"domain.io/foo"]`. ([#131574](https://github.com/kubernetes/kubernetes/pull/131574), [@enj](https://github.com/enj)) [SIG API Machinery and Auth]

- Fixed a regression in default configurations, which enabled PodDisruptionConditions by default,