([#121834](https://github.com/kubernetes/kubernetes/pull/121834), [@vaibhav2107](https://github.com/vaibhav2107))
- Changed the API server so that for admission webhooks that have a URL matching the hostname 'localhost' or a loopback IP address, the connection supports HTTP/2 where it could be negotiated.
   ([#122558](https://github.com/kubernetes/kubernetes/pull/122558), [@linxiulei](https://github.com/linxiulei))

- kubelet: change `node-lease-renew-interval` to 0.25 of lease-renew-duration ([#80429](https://github.com/kubernetes/kubernetes/pull/80429), [@gaorong](https://github.com/gaorong))
- Attempt to set the kubelet's hostname & internal IP if `--cloud-provider=external` and no node addresses exists ([#75229](https://github.com/kubernetes/kubernetes/pull/75229), [@andrewsykim](https://github.com/andrewsykim))

### Scheduling

- Node Problem Detector is now available for GCE Windows nodes. ([#101539](http...

## Changelog since v1.8.1

### Other notable changes

* Allow for configuring etcd hostname in the manifest ([#54403](https://github.com/kubernetes/kubernetes/pull/54403), [@wojtek-t](https://github.com/wojtek-t))

pkg os, func Getgroups() ([]int, error)
pkg os, func Getpagesize() int
pkg os, func Getpid() int
pkg os, func Getppid() int
pkg os, func Getuid() int
pkg os, func Getwd() (string, error)
pkg os, func Hostname() (string, error)
pkg os, func IsExist(error) bool
pkg os, func IsNotExist(error) bool
pkg os, func IsPathSeparator(uint8) bool
pkg os, func IsPermission(error) bool
pkg os, func Lchown(string, int, int) error