- Fixes a bug that when there is a "connection refused" error, the reflector's ListAndWatch func will return directly but what expected is that sleep 1 second and rewatch since the specified resourceVersion.
  ([#81634](https://github.com/kubernetes/kubernetes/pull/81634), [@likakuli](https://github.com/likakuli))

cluster-wide seccomp defaults, the kubelet uses the `RuntimeDefault` seccomp profile by default, rather than than `Unconfined`. This allows enhancing the default cluster wide workload security of the Kubernetes deployment. Security administrators will now sleep better knowing there is some security by default for the workloads.

To learn more about the feature, please refer to the official [seccomp tutorial](https://kubernetes.io/docs/tutorials/clusters/seccomp/#enable-the-use-of-runtimedefau...

 - Insert a debug container in clusters that don’t have ephemeral containers enabled 
 - Modify a crashing container for easier debugging by changing its image, for example to busybox, or its command, for example, to `sleep 1d` so you have time to `kubectl exec`.
 - Inspect configuration files on a node's host filesystem

  is removed in `v1.29`. Migrated `kube-scheduler` configuration files to `kubescheduler.config.k8s.io/v1`.' ([#119994](https://github.com/kubernetes/kubernetes/pull/119994), [@SataQiu](https://github.com/SataQiu))
- A new sleep action for the `PreStop` lifecycle hook was added, allowing containers to pause for a specified duration before termination. ([#119026](https://github.com/kubernetes/kubernetes/pull/119026), [@AxeZhan](https://github.com/AxeZhan))

- A new metric `lifecycle_handler_sleep_terminated_total` is added to record how many times LifecycleHandler sleep got unexpectedly terminated. ([#122456](https://github.com/kubernetes/kubernetes/pull/122456), [@AxeZhan](https://github.com/AxeZhan))