* `v1beta1` RoleBinding/ClusterRoleBinding subjects changed `apiVersion` to `apiGroup` to fully-qualify a subject. ServiceAccount subjects default to an apiGroup of `""`, User and Group subjects default to an apiGroup of `"rbac.authorization.k8s.io"`. ([#41184](https://github.com/kubernetes/kubernetes/pull/41184), [@liggitt](https://github.com/liggitt))

- Kubeadm: changed the "system:masters" Group in the apiserver-kubelet-client.crt certificate Subject to be "kubeadm:cluster-admins" which is a less privileged Group. ([#121837](https://github.com/kubernetes/kubernetes/pull/121837), [@neolit123](https://github.com/neolit123))

  remove unused rules immediately once they are no longer used.)

  (The threshold for "large" used here is currently "1000 endpoints" but
  this is subject to change.) ([#110334](https://github.com/kubernetes/kubernetes/pull/110334), [@danwinship](https://github.com/danwinship))

- Add auth API to get self subject attributes (new selfsubjectreviews API is added). 

- Kubernetes is now built with golang 1.15.0-rc.1.

  - Use of the `--node-labels` flag to set labels under the `kubernetes.io/` and `k8s.io/` prefix will be subject to restriction by the `NodeRestriction` admission plugin in future releases. [See admission plugin documentation](https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#noderestriction) for allowed labels. ([#68267](https:...

- Kubectl set resources will no longer return an error if passed an empty change for a resource. kubectl set subject will no longer return an error if passed an empty change for a resource. ([#85490](https://github.com/kubernetes/kubernetes/pull/85490), [@sallyom](https://github.com/sallyom))

- Replaced *_admission_latencies_milliseconds_summary and *_admission_latencies_milliseconds metrics because they were reporting seconds rather than milliseconds. They were also subject to multiple naming guideline violations (units should be in base units and "duration" is the best practice labelling to measure the time a request takes). Please convert to use *_admission_duration_seconds and *_admission_duration_seconds_summary,...

  * PodSecurityPolicy admission sets `podsecuritypolicy.admission.k8s.io/admit-policy` and `podsecuritypolicy.admission.k8s.io/validate-policy` annotations containing the name of the policy that allowed a pod to be...

    * be created in 192.168.0.0./16 and 172.16.0.0/12 while preserving the container IPs (which would be lost before).
* `set selector` and `set subject` no longer print "running in local/dry-run mode..." at the top, so their output can be piped as valid yaml or json ([#46507](https://github.com/kubernetes/kubernetes/pull/46507), [@bboreham](https://github.com/bboreham))