- Added support for in-place vertical scaling of Pods with sidecars (containers defined within `initContainers` where the `restartPolicy` is set to `Always`). ([#128367](https://github.com/kubernetes/kubernetes/pull/128367), [@vivzbansal](https://github.com/vivzbansal)) [SIG API Machinery,...

- Added a detailed event for in-place pod vertical scaling completed, improving cluster management and debugging. ([#130387](https://github.com/kubernetes/kubernetes/pull/130387), [@shiya0705](https://github.com/shiya0705)) [SIG API Machinery, Apps, Autoscaling, Node, Scheduling and Testing]

- Added CEL expressions to `v1alpha1 AuthenticationConfiguration`. ([#121078](https://github.com/kubernetes/kubernetes/pull/121078), [@aramase](https://github.com/aramase))
- Added Windows support for InPlace Pod Vertical Scaling feature. ([#112599](https://github.com/kubernetes/kubernetes/pull/112599), [@fabi200123](https://github.com/fabi200123)) [SIG Autoscaling, Node, Scalability, Scheduling and Windows]

- Extend discovery GroupManager with Group lister interface ([#127524](https://github.com/kubernetes/kubernetes/pull/127524), [@mjudeikis](https://github.com/mjudeikis)) [SIG API Machinery]
- Fixed: Avoid overwriting in-pod vertical scaling updates on systemd daemon reloads when using systemd ([#124216](https://github.com/kubernetes/kubernetes/pull/124216), [@iholder101](https://github.com/iholder101)) [SIG Node]

* kube-proxy needs to be configured to override hostname in some environments. ([#857](https://github.com/kubernetes/kubeadm/issues/857), [@detiber](https://github.com/detiber))
* There's a known issue where the Vertical Pod Autoscaler will radically change implementation in 1.12, so users of VPA (alpha) in 1.11 are warned that they will not be able to automatically migrate their VPA configs from 1.11 to 1.12.


## Before Upgrading