Depending on the value returned from QueueingHintFn, the scheduling queue changes how it queues each Pod:
  - if more than one QueueingHintFn returns QueueImmediately, it queues Pod to activeQ.

* StatefulSet: The deprecated `pod.alpha.kubernetes.io/initialized` annotation for interrupting StatefulSet Pod management is now ignored. If you were setting it to `true` or leaving it unset, no action is required. However, if you were setting it to `false`, be aware that previously-dormant StatefulSets may become active after upgrading. ([#49251](https://github.com/kubernetes/kubernetes/pull/49251), [@enisoc](https://github.com/enisoc))

- Kubeadm: remove 'kubeadm upgrade node config' command since it was deprecated in v1.15, please use 'kubeadm upgrade node phase kubelet-config' instead ([#87975](https://github.com/kubernetes/kubernetes/pull/87975), [@SataQiu](https://github.com/SataQiu)) [SIG Cluster Lifecycle]

* Fixes bug in DaemonSetController causing it to stop processing some DaemonSets for 5 minutes after node removal. ([#76060](https://github.com/kubernetes/kubernetes/pull/76060), [@krzysztof-jastrzebski](https://github.com/krzysztof-jastrzebski))

- Kubeadm no longer removes /etc/cni/net.d as it does not install it. Users should remove files from it manually or rely on the component that created them ([#83950](https://github.com/kubernetes/kubernetes/pull/83950), [@yastij](https://github.com/yastij))

* In case StorageObjectInUse feature is disabled and Persistent Volume (PV) or Persistent Volume Claim (PVC) contains a finalizer and the PV or PVC is deleted it is not automatically removed from the system. Now, it is automatically removed. ([#62938](https://github.com/kubernetes/kubernetes/pull/62938), [@pospispa](https://github.com/pospispa))

  - https://github.com/kubernetes-sigs/kustomize/pull/4985: If you previously included .git in an AWS or Azure URL, we will no longer automatically...

 - Kubeadm: during "init"...

    *   Change `node.alpha.kubernetes.io/unreachable` to  `node.kubernetes.io/unreachable`
*   The `node.kubernetes.io/memory-pressure` taint now respects the configured whitelist.  To use it, you must add it to the whitelist.([#55251](https://github.com/kubernetes/kubernetes/pull/55251),[ @deads2k](https://github.com/deads2k))
*   Refactor kube-scheduler configuration ([#52428](https://github.com/kubernetes/kubernetes/pull/52428))

has been deprecated as part of the deprecation of Heapster. Instead, you may use the [metrics server](https://github.com/kubernetes-incubator/metrics-server). It's a simplified heapster that is able to gather and serve current metrics values. It provides the Metrics API that is used by `kubectl top`, and horizontal pod autoscaler. Note that it doesn't include some features of Heapster, such as short term metrics for graphs in kube-dashboard and dedicated push sinks, which proved hard to maintain and...