- OpenAPI spec now correctly marks delete request's body parameter as optional ([#70032](https://github.com/kubernetes/kubernetes/pull/70032), [@iamneha](https://github.com/iamneha))

- Added a redundant process to remove tracking finalizers from Pods that belong to Jobs. The process kicks in after the control plane marks a Job as finished. ([#119944](https://github.com/kubernetes/kubernetes/pull/119944), [@Sharpz7](https://github.com/Sharpz7))

  * Fix the bug where StartedAt time is not reported for exited containers. ([#45977](https://github.com/kubernetes/kubernetes/pull/45977), [@yujuhong](https://github.com/yujuhong))

* Changes/deprecations

  * Marks the Kubelet's `--master-service-namespace` flag deprecated ([#44250](https://github.com/kubernetes/kubernetes/pull/44250), [@mtaufen](https://github.com/mtaufen))

- **Admission webhooks:** Admission webhooks are in widespread use as a Kubernetes extensibility mechanism and have been available in beta since the 1.9 release. The 1.16 release marks the graduation of admission webhooks to general availability (GA).