* The new ReplicaSet API (Beta) in the Extensions API group is similar to
ReplicationController, but its [selector](http://kubernetes.io/docs/user-guide/labels/#label-selectors) is more general (supports set-based selector; whereas ReplicationController
only supports equality-based selector).
  * Scale subresource support is now expanded to ReplicaSets along with
ReplicationControllers and Deployments. Scale now supports two different types

  // Defaults to 1.
  // More info: https://kubernetes.io/docs/concepts/workloads/controllers/replicationcontroller/#what-is-a-replicationcontroller
  // +optional
  optional int32 replicas = 1;

  // Minimum number of seconds for which a newly created pod should be ready
  // without any of its container crashing, for it to be considered available.

- Added warnings about workload resources (Pods, ReplicaSets, Deployments, Jobs, CronJobs, or ReplicationControllers) whose names are not valid DNS labels. ([#114412](https://github.com/kubernetes/kubernetes/pull/114412), [@thockin](https://github.com/thockin))

  // Defaults to 1.
  // More info: https://kubernetes.io/docs/concepts/workloads/controllers/replicationcontroller/#what-is-a-replicationcontroller
  // +optional
  optional int32 replicas = 1;

  // Minimum number of seconds for which a newly created pod should be ready
  // without any of its container crashing, for it to be considered available.

  // Defaults to 1.
  // More info: https://kubernetes.io/docs/concepts/workloads/controllers/replicationcontroller/#what-is-a-replicationcontroller
  // +optional
  optional int32 replicas = 1;

  // Minimum number of seconds for which a newly created pod should be ready
  // without any of its container crashing, for it to be considered available.

  // Data is a bit array containing all allocated addresses in the previous segment.
  optional bytes data = 3;
}

// ReplicationController represents the configuration of a replication controller.
message ReplicationController {
  // If the Labels of a ReplicationController are empty, they are defaulted to
  // be the same as the Pod(s) that the replication controller manages.

    *   The view role includes read permissions on poddisruptionbudget.policy resources.
*   RBAC rules can now match the same subresource on any resource using the form `*/(subresource)`. For example, `*/scale` matches requests to `replicationcontroller/scale`. ([#53722](https://github.com/kubernetes/kubernetes/pull/53722),[ @deads2k](https://github.com/deads2k))

* Fix premature return ([#49834](https://github.com/kubernetes/kubernetes/pull/49834), [@guoshimin](https://github.com/guoshimin))
* StatefulSet uses scale subresource when scaling in accord with ReplicationController, ReplicaSet, and Deployment implementations. ([#49168](https://github.com/kubernetes/kubernetes/pull/49168), [@crimsonfaith91](https://github.com/crimsonfaith91))

- Track ownership of scale subresource for all scalable resources i.e. Deployment, ReplicaSet, StatefulSet, ReplicationController, and Custom Resources. ([#98377](https://github.com/kubernetes/kubernetes/pull/98377), [@nodo](https://github.com/nodo)) [SIG API Machinery and Testing]

### Feature