* You can now set `VolumeMount.Propagation` to `Bidirectional` to enable a particular mount for a container to propagate itself to the host or other containers.

* [alpha] Improve Flex volume deployment

  * Flex volume driver deployment is simplified in the following ways:

    * New driver files can now be automatically discovered and initialized without requiring a kubelet or controller-manager restart.

- When describing deployments, `OldReplicaSets` now always shows all replicasets controlled the deployment, not just those that still have replicas available. ([#113083](https://github.com/kubernetes/kubernetes/pull/113083), [@llorllale](https://github.com/llorllale)) [SIG CLI]

- Pods which set `hostNetwork: true` and declare ports, get the `hostPort` field set automatically. Previously this would happen in the PodTemplate of a Deployment, DaemonSet or other workload API.  Now `hostPort` will only be set when an actual Pod is being created.  If this presents a problem, setting the feature gate "DefaultHostNetworkHostPortsInPodTemplates" to true will revert this behavior.  Please...

- The deprecated kube-controller-manager flag '--deployment-controller-sync-period' has been removed, it is not used by the deployment controller. ([#107178](https://github.com/kubernetes/kubernetes/pull/107178), [@SataQiu](https://github.com/SataQiu))

- The TopologySpreadConstraints will be shown in describe command for pods, deployments, daemonsets, etc. ([#109563](https://github.com/kubernetes/kubernetes/pull/109563), [@ardaguclu](https://github.com/ardaguclu))

  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.'
   ([#112011](https://github.com/kubernetes/kubernetes/pull/112011), [@pbeschetnov](https://github.com/pbeschetnov))
- 'Pod Security admission: the pod-security `warn` level will now default to
  the `enforce` level.'

### Documentation

- Added descriptions and examples for the situation of using `kubectl rollout restart` without specifying a particular deployment. ([#120118](https://github.com/kubernetes/kubernetes/pull/120118), [@Ithrael](https://github.com/Ithrael))