- When the `PodObservedGenerationTracking` feature gate was set,...

  name of controllers that can be turned on/off that are passed to the `--controllers`
  flag (e.g., `pod-garbage-collector-controller`). The old names (eg `podgc`) are
  also accepted and aliased to the new names. ([#115813](https://github.com/kubernetes/kubernetes/pull/115813), [@atiratree](https://github.com/atiratree))
- `kubeadm`: Introduced a new feature gate `UpgradeAddonsBeforeControlPlane` to

- Cleanup: removed `getStorageAccountName` warning messages.
   ([#121983](https://github.com/kubernetes/kubernetes/pull/121983), [@andyzhangx](https://github.com/andyzhangx))
- Client-go: Optimized leaders renewing leases by updating leader lock optimistically without getting the record from the API server first. Also, a new metric `leader_election_slowpath_total` was added to allow users to monitor how many leader elections are updated non-optimistically.

### Bug or Regression

- Avoid GCE API calls when initializing GCE CloudProvider for Kubelets.
  Avoid unnecessary GCE API calls when adding IP alises or reflecting them in Node object in GCE cloud provider. ([#96863](https://github.com/kubernetes/kubernetes/pull/96863), [@tosi3k](https://github.com/tosi3k)) [SIG Apps, Cloud Provider and Network]

- Namespace editors and admins can now create leases.coordination.k8s.io and should use this type for leaderelection instead of configmaps. ([#111515](https://github.com/kubernetes/kubernetes/pull/111515), [@deads2k](https://github.com/deads2k)) [SIG API Machinery and Auth]

- The namespace editors and admins can now create leases.coordination.k8s.io and should use this type for leaderelection instead of configmaps. ([#111472](https://github.com/kubernetes/kubernetes/pull/111472), [@deads2k](https://github.com/deads2k))

- Fixes a bug of identifying the correct containerd process. ([#97888](https://github.com/kubernetes/kubernetes/pull/97888), [@pacoxu](https://github.com/pacoxu))
- Fixes add-on manager leader election to use leases instead of endpoints, similar to what kube-controller-manager does in 1.20 ([#98968](https://github.com/kubernetes/kubernetes/pull/98968), [@liggitt](https://github.com/liggitt))