* StatefulSet: The deprecated `pod.alpha.kubernetes.io/initialized` annotation for interrupting the StatefulSet Pod management is now ignored. StatefulSets with this annotation set to `true` or with no value will behave just as they did in previous versions. Dormant StatefulSets with the annotation set to `false` will become active after upgrading.

- `StatefulSetAutoDeletePVC` feature gate promoted to beta. ([#116501](https://github.com/kubernetes/kubernetes/pull/116501), [@mattcary](https://github.com/mattcary))
- `StatefulSet` names must be DNS labels, rather than subdomains. Any `StatefulSet`
  which took advantage of subdomain validation (by having dots in the name) can't
  possibly have worked, because we eventually set `pod.spec.hostname` from the `StatefulSetName`,

- Fixes a panic in kube-controller-manager handling StatefulSet objects when revisionHistoryLimit is negative ([#129325](https://github.com/kubernetes/kubernetes/pull/129325), [@ardaguclu](https://github.com/ardaguclu)) [SIG Apps]

- Validation now requires new StatefulSets with a `.spec.serviceName` field value to pass DNS1123 validation. Previously created StatefulSets with an invalid `.spec.serviceName` field value could not create any pods, and should be deleted.

- StatefulSet pods now have the pod index set as a pod label `statefulset.kubernetes.io/pod-index`. ([#119232](https://github.com/kubernetes/kubernetes/pull/119232), [@danielvegamyhre](https://github.com/danielvegamyhre)) [SIG Apps]

- Add `PersistentVolumeClaimDeletePoilcy` to StatefulSet API. ([#99378](https://github.com/kubernetes/kubernetes/pull/99378), [@mattcary](https://github.com/mattcary))

### Bug or Regression

- Added `podSpec` validation for creating `StatefulSet`. ([#131790](https://github.com/kubernetes/kubernetes/pull/131790), [@chengjoey](https://github.com/chengjoey)) [SIG Apps, Etcd and Testing]

- Fixed StatefulSet to show the valid status even if the new replica creation fails. ([#112084](https://github.com/kubernetes/kubernetes/pull/112084), [@gjkim42](https://github.com/gjkim42)) [SIG Apps and Testing]

- Fixed a 1.25.12 regression where kube-controller-manager can crash when StatefulSet with Parallel policy and PVC labels is scaled up. ([#121187](https://github.com/kubernetes/kubernetes/pull/121187), [@aleksandra-malinowska](https://github.com/aleksandra-malinowska)) [SIG Apps]

- Fixed a 1.26.7 regression where kube-controller-manager can crash when StatefulSet with Parallel policy and PVC labels is scaled up. ([#121186](https://github.com/kubernetes/kubernetes/pull/121186), [@aleksandra-malinowska](https://github.com/aleksandra-malinowska)) [SIG Apps]