- Fix remove the etcd member from the cluster during a kubeadm reset. ([#79326](https://github.com/kubernetes/kubernetes/pull/79326), [@bradbeam](https://github.com/bradbeam))

  specific point in time, rather than a document that may change over time.
  
  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>

- Kubeadm: warn but do not error out on missing "ca.key" files for root CA, front-proxy CA and etcd CA, during "kubeadm join --control-plane" if the user has provided all certificates, keys and kubeconfig files which require signing with the given CA keys. ([#94988](https://github.com/kubernetes/kubernetes/pull/94988), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]...

- Kube-apiserver: the AuthenticationConfiguration type accepted in `--authentication-config` files has been promoted to `apiserver.config.k8s.io/v1beta1`. ([#123696](https://github.com/kubernetes/kubernetes/pull/123696), [@aramase](https://github.com/aramase)) [SIG API Machinery, Auth and Testing]

  specific point in time, rather than a document that may change over time.
  
  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>

* Fix error in `kubeadm join --discovery-file` when using discovery files with embedded credentials ([#80675](https://github.com/kubernetes/kubernetes/pull/80675), [@fabriziopandini](https://github.com/fabriziopandini))

* Restored the ability of kubectl running inside a pod to consume resource files specifying a different namespace than the one the pod is running in. ([#44862](https://github.com/kubernetes/kubernetes/pull/44862), [@liggitt](https://github.com/liggitt))

  // +optional
  // +listType=atomic
  repeated DownwardAPIVolumeFile items = 1;

  // Optional: mode bits to use on created files by default. Must be a
  // Optional: mode bits used to set permissions on created files by default.
  // Must be an octal value between 0000 and 0777 or a decimal value between 0 and 511.

## Changelog since v1.8.14

### Action Required

* ACTION REQUIRED: Kubernetes JSON deserializer is now case-sensitive to restore compatibility with pre-1.8 servers. If your config files contains fields with wrong case, the config files will be now invalid. ([#65410](https://github.com/kubernetes/kubernetes/pull/65410), [@nikhita](https://github.com/nikhita))

### Other notable changes

i.content.every(t=>typeof t=="string"?!0:!(typeof t?.raw!="string"||t?.extension&&typeof t?.extension!="string"));if(typeof i.content=="object"&&i.content!==null){if(Object.keys(i.content).some(t=>!["files","relative","extract","transform"].includes(t)))return!1;if(Array.isArray(i.content.files)){if(!i.content.files.every(t=>typeof t=="string"?!0:!(typeof t?.raw!="string"||t?.extension&&typeof t?.extension!="string")))return!1;if(typeof i.content.extract=="object"){for(let t of Object.values(i.content.extract))if(typeof...