- The 404 request handler for the GCE Ingress load balancer now exports prometheus metrics, including:

  - `http_404_request_total` (the number of 404 requests handled)
  - `http_404_request_duration_ms` (the amount of time the server took to respond in ms)

* apiserver: fixes handling and logging of panics in REST handlers to prevent crashes ([#71076](https://github.com/kubernetes/kubernetes/pull/71076), [@liggitt](https://github.com/liggitt))

- Fixed an issue with stuck connections handling error responses ([#71412](https://github.com/kubernetes/kubernetes/pull/71412), [@liggitt](https://github.com/liggitt))
- apiserver: fixed handling and logging of panics in REST handlers ([#71076](https://github.com/kubernetes/kubernetes/pull/71076), [@liggitt](https://github.com/liggitt))

* Default resourceGroup should be used when the value of annotation azure-load-balancer-resource-group is an empty string. ([#79514](https://github.com/kubernetes/kubernetes/pull/79514), [@feiskyer](https://github.com/feiskyer))
* The CRD handler now properly re-creates stale CR storage to reflect CRD update. ([#79114](https://github.com/kubernetes/kubernetes/pull/79114), [@roycaihw](https://github.com/roycaihw))

- 'Container `preStop` and `postStart` lifecycle handlers using `httpGet` now
  honor the specified `scheme` and `headers` fields. This enables setting custom
  headers and changing the scheme to `HTTPS`, consistent with container
  startup/readiness/liveness probe capabilities. Lifecycle handlers configured
  with `scheme: HTTPS` that encounter errors indicating the endpoint is actually

    * Introduce a RuntimeClass v1beta1 API. This new beta API renames `runtimeHandler` to `handler`, makes it a required field, and cuts out the spec (handler is a top-level field).

* Fix a scheduler panic due to internal cache inconsistency ([#71063](https://github.com/kubernetes/kubernetes/pull/71063), [@Huang-Wei](https://github.com/Huang-Wei))
* apiserver: fixes handling and logging of panics in REST handlers to prevent crashes ([#71076](https://github.com/kubernetes/kubernetes/pull/71076), [@liggitt](https://github.com/liggitt))

- Fixed missing delete events on informer re-lists to ensure all delete events were correctly emitted and using the latest known object state, so that all event handlers and stores always reflect the actual apiserver state as best as possible ([#115620](https://github.com/kubernetes/kubernetes/pull/115620), [@odinuge](https://github.com/odinuge))

### Bug or Regression

- Adds node event handlers to dual stack kube-proxy implementation to fix Topology Aware Hints. ([#101054](https://github.com/kubernetes/kubernetes/pull/101054), [@robscott](https://github.com/robscott)) [SIG Network]

* Re-add /healthz/ping handler in genericapiserver ([#38603](https://github.com/kubernetes/kubernetes/pull/38603), [@sttts](https://github.com/sttts))