- For all kinds in the API group version, a spec.selector default value is no longer
 available, because it's incompatible with `kubectl
 apply` and strategic merge patch. You must explicitly set the spec.selector value
 in your manifest. An object with a spec.selector value that does not match the labels in
 its spec.template is invalid.

 - Selector mutation is disabled for all kinds in the

- Introduces new alpha functionality to the reflector, allowing user to enable API streaming.
  
  To activate this feature, users can set the `ENABLE_CLIENT_GO_WATCH_LIST_ALPHA` environmental variable.
  It is important to note that the server must support streaming for this feature to function properly.
  If streaming is not supported by the server, the reflector will revert to the previous method

  IPv6 IPs. ([#121008](https://github.com/kubernetes/kubernetes/pull/121008), [@danwinship](https://github.com/danwinship)) [SIG Network]
- Fixed an issue to not drain all the pods in a namespace when an empty-selector i.e. "{}" is specified in a Pod Disruption Budget (PDB) ([#121131](https://github.com/kubernetes/kubernetes/pull/121131), [@sairameshv](https://github.com/sairameshv)) [SIG Apps]

  don't match the node affinity/selector. This may lead to unschedulable pods if you previously had pods
  matching the spreading selector on those excluded nodes (not matching the node affinity/selector),
  especially when the `topologyKey` is not node-level. Revisit the node affinity and/or pod selector in the

- Make kubectl diff --prune behave correctly with the --selector/-l flag ([#116147](https://github.com/kubernetes/kubernetes/pull/116147), [@nathanmartins](https://github.com/nathanmartins)) [SIG CLI and Testing]

   ([#109525](https://github.com/kubernetes/kubernetes/pull/109525), [@jonyhy96](https://github.com/jonyhy96))

### Feature

- 'Added selector validation to `HorizontalPodAutoscaler`: when multiple HPAs
  select the same set of Pods, scaling now will be disabled for those HPAs with
  the reason `AmbiguousSelector`. This change also covers a case when multiple HPAs
  point to the same deployment.'

- Aggregated discovery supports both `v2beta1` and v2 types and feature is promoted to GA. ([#122882](https://github.com/kubernetes/kubernetes/pull/122882), [@Jefftree](https://github.com/Jefftree))

- Fixed an issue related to not draining all the pods in a namespace when an empty selector, i.e., "{}," is specified in a Pod Disruption Budget (PDB). ([#119732](https://github.com/kubernetes/kubernetes/pull/119732), [@sairameshv](https://github.com/sairameshv))