* CustomResourceDefinitions: OpenAPI v3 validation schemas containing `$ref`references are no longer permitted (valid references could not be constructed previously because property ids were not permitted either). Before upgrading, ensure CRD definitions do not include those `$ref` fields. ([#58438](https://github.com/kubernetes/kubernetes/pull/58438), [@carlory](https://github.com/carlory))

  - NetworkPolicy resources will no longer be served from `extensions/v1beta1` in v1.16. Migrate use to the `networking.k8s.io/v1` API, available since v1.8. Existing persisted data can be retrieved via the `networking.k8s.io/v1` API.

### Feature

  - PriorityClass resources will no longer be served from `scheduling.k8s.io/v1beta1` and `scheduling.k8s.io/v1alpha1` in v1.17. Migrate to the `scheduling.k8s.io/v1` API, available since v1.14. Existing persisted data can be retrieved via the `scheduling.k8s.io/v1` API.

   * serializable.
   *
   * <p>This method's signature will not permit you to convert a {@code NavigableMap<? extends K,
   * V>} to a {@code NavigableMap<K, V>}. If it permitted this, the returned map's {@code
   * comparator()} method might return a {@code Comparator<? extends K>}, which works only on a
   * particular subtype of {@code K}, but promise that it's a {@code Comparator<? super K>}, which

   * serializable.
   *
   * <p>This method's signature will not permit you to convert a {@code NavigableMap<? extends K,
   * V>} to a {@code NavigableMap<K, V>}. If it permitted this, the returned map's {@code
   * comparator()} method might return a {@code Comparator<? extends K>}, which works only on a
   * particular subtype of {@code K}, but promise that it's a {@code Comparator<? super K>}, which

- Kube-apiserver: The NodeRestriction admission plugin now restricts Node labels kubelets are permitted to set when creating a new Node to the `--node-labels` parameters accepted by kubelets in 1.16+. ([#90307](https://github.com/kubernetes/kubernetes/pull/90307), [@liggitt](https://github.com/liggitt)) [SIG Auth and Node]

    The Panther took pie-crust, and gravy, and meat,
    While the Owl had the dish as its share of the treat.
    When the pie was all finished, the Owl, as a boon,
    Was kindly permitted to pocket the spoon:
    While the Panther received knife and fork with a growl,
    And concluded the banquet--]

  `What IS the use of repeating all that stuff,' the Mock Turtle

- Kube-apiserver: events created via the `events.k8s.io` API group for cluster-scoped objects are now permitted in the default namespace as well for compatibility with events clients and the `v1` API ([#100125](https://github.com/kubernetes/kubernetes/pull/100125), [@h4ghhh](https://github.com/h4ghhh))

- The `kube-scheduler` component config `v1beta2` API available