- Migrated the bootstrap signer controller and the token cleaner controller (within `kube-controller-manager`) to use [contextual logging](https://k8s.io/docs/concepts/cluster-administration/system-logs/#contextual-logging). ([#113464](https://github.com/kubernetes/kubernetes/pull/113464),...

upgrading, and deleting clusters.

For the 1.8 release, SIG Cluster Lifecycle continued to focus on expanding the
capabilities of kubeadm, which is both a user-facing tool to manage clusters
and a building block for higher-level provisioning systems. Starting
with the 1.8 release, kubeadm supports a new upgrade command and includes alpha
support for self hosting the cluster control plane.

- ACTION_REQUIRED

- Kube-apiserver: gzip compression switched from level 4 to level 1 to improve large list call latencies in exchange for higher network bandwidth usage (10-50% higher). This increases the headroom before very large unpaged list calls exceed request timeout limits. ([#112399](https://github.com/kubernetes/kubernetes/pull/112399), [@shyamjvs](https://github.com/shyamjvs)) [SIG API Machinery]

- Kube-apiserver: gzip compression switched from level 4 to level 1 to improve large list call latencies in exchange for higher network bandwidth usage (10-50% higher). This increases the headroom before very large unpaged list calls exceed request timeout limits. ([#112398](https://github.com/kubernetes/kubernetes/pull/112398), [@shyamjvs](https://github.com/shyamjvs)) [SIG API Machinery]

- Addressed an issue where a JWT authenticator set up via `--authentication-config` would encounter failures in verifying tokens not signed with RS256. ([#123282](https://github.com/kubernetes/kubernetes/pull/123282), [@enj](https://github.com/enj))

- Fixed CEL estimated cost of `replace()` to handle a zero length replacement string correctly.
  Previously this would cause the estimated cost to be higher than it should be. ([#120097](https://github.com/kubernetes/kubernetes/pull/120097), [@jpbetz](https://github.com/jpbetz)) [SIG API Machinery]

- Kube-apiserver: `gzip` compression switched from level 4 to level 1 to improve large list call latencies in exchange for higher network bandwidth usage (10-50% higher). This increases the headroom before very large unpaged list calls exceed request timeout limits. ([#112299](https://github.com/kubernetes/kubernetes/pull/112299), [@shyamjvs](https://github.com/shyamjvs))