The scheduling hints allow the scheduler to only retry scheduling a `Pod`
  that was previously rejected by the `NodeAffinity` plugin if a new `Node` or a `Node` update matches the `Pod`'s node affinity. ([#119155](https://github.com/kubernetes/kubernetes/pull/119155), [@carlory](https://github.com/carlory))
- `kubeadm`: promoted feature gate `EtcdLearnerMode` to `beta`. Learner mode for

- Kube-apiserver: ensures the namespace of objects sent to admission webhooks matches the request namespace. Previously, objects without a namespace set would have the request namespace populated after mutating admission, and objects with a namespace that did not match the request namespace would be rejected after admission. ([#94...

  * Mediates issue [#36859](https://github.com/kubernetes/kubernetes/pull/36859). StatefulSet only acts on Pods whose identity matches the StatefulSet, providing a partial mediation for overlapping controllers.

### Taints and Tolerations

- Azurefile: Normalize share name to not include capital letters ([#100731](https://github.com/kubernetes/kubernetes/pull/100731), [@kassarl](https://github.com/kassarl)) [SIG Cloud Provider and Storage]
- EndpointSlice IP validation now matches Endpoints IP validation. ([#101084](https://github.com/kubernetes/kubernetes/pull/101084), [@robscott](https://github.com/robscott)) [SIG Apps and Network]

- The alpha `Initializers` admission plugin is no longer enabled by default. This matches the off-by-default behavior of the alpha API which drives initializer behavior. ([#66039](https://github.com/kubernetes/kubernetes/pull/66039), [@liggitt](https://github.com/liggitt))

* Pod affinity `nodeSelectorTerm.matchExpressions` may now be empty, and works as previously documented: nil or empty `matchExpressions` matches no objects in scheduler. ([#62448](https://github.com/kubernetes/kubernetes/pull/62448), [@k82cn](https://github.com/k82cn))

- Add scheduling support for RuntimeClasses. RuntimeClasses can now specify nodeSelector...

- Remove `NodeLease` feature gate that was graduated and locked to stable in 1.17 release....

- The `EndpointSlice` IP validation now matches `Endpoints` IP validation. ([#101084](https://github.com/kubernetes/kubernetes/pull/101084), [@robscott](https://github.com/robscott))

  `You shan't be beheaded!' said Alice, and she put them into a
large flower-pot that stood near.  The three soldiers wandered
about for a minute or two, looking for them, and then quietly
marched off after the others.

  `Are their heads off?' shouted the Queen.

  `Their heads are gone, if it please your Majesty!' the soldiers
shouted in reply.