* You *MUST* set `--anonymous-auth=false` flag on your kube-apiserver unless you are a developer testing this feature and understand it.
  If you do not, you risk allowing unauthorized users to access your apiserver.
  * You *MUST* set `--anonymous-auth=false` flag on your federation apiserver unless you are a developer testing this feature and understand it.
    If you do not, you risk allowing unauthorized users to access your federation apiserver.

- RemoteCommand feature gates for kubectl exec, cp, and attach over WebSockets are now enabled by default (Beta):
  - Server-side feature gate: `TranslateStreamCloseWebsocketRequests`
  - Client-side (kubectl) feature gate: `KUBECTL_REMOTE_COMMAND_WEBSOCKETS`

- Online volume expansion (ExpandInUsePersistentVolumes) is now a beta feature. As such, it is enabled by default. ([#77755](https://github.com/kubernetes/kubernetes/pull/77755), [@gnufied](https://github.com/gnufied))

support the alpha `scheduler.alpha.kubernetes.io/affinity` annotation on the Pod if you explicitly enable the alpha feature "AffinityInAnnotations", but it will be removed in a future release. When you upgrade to 1.6, if you have not enabled the alpha feature, then the scheduler will use the `affinity` field in PodSpec and will ignore the annotation. If you have enabled the alpha feature, then the scheduler will use the `affinity` field in PodSpec if it is present, and otherwise will use the annotation....

## Changelog since v1.4.0-alpha.2

### Action Required

* Moved init-container feature from alpha to beta. ([#31026](https://github.com/kubernetes/kubernetes/pull/31026), [@erictune](https://github.com/erictune))
    * Security Action Required:

* PodReadinessGate feature is now GA. The feature gate will not allow disabling it. ([#74434](https://github.com/kubernetes/kubernetes/pull/74434), [@freehan](https://github.com/freehan))

- Removed the `CronJobTimeZone` feature gate (the feature is stable and always enabled)
  - Removed the `JobMutableNodeSchedulingDirectives` feature gate (the feature is stable and always enabled)

- Lock ServerSideApply feature gate to true with the feature already being GA. ([#112748](https://github.com/kubernetes/kubernetes/pull/112748), [@wojtek-t](https://github.com/wojtek-t)) [SIG API Machinery, Apps, Instrumentation and Testing]

  * vendor volumes into a pod. It expects vendor drivers are installed in the
volume plugin path on each kubelet node. This is an alpha feature and may
change in future.
  * Kubelet exposes a new Alpha metrics API - /stats/summary in a user friendly format with reduced system overhead. The measurement is done in PR [#22542](https://github.com/kubernetes/kubernetes/pull/22542).

## **Notable Features**

Features for this release were tracked via the use of the [kubernetes/features](https://github.com/kubernetes/features) issues repo. Each Feature issue is owned by a Special Interest Group from [kubernetes/community](https://github.com/kubernetes/community)