`client-certificate: /var/lib/kubelet/pki/kubelet-client-current.pem` and `client-key: /var/lib/kubelet/pki/kubelet-client-current.pem`, replacing the embedded client certificate and key. ([#84118](https://github.com/kubernetes/kubernetes/pull/84118), [@neolit123](https://github.com/neolit123))

`kubelet-client.crt`.  Subsequent certificates created by cert rotation were created in a combined PEM file that was atomically rotated as `kubelet-client-DATE.pem` in that directory, which meant clients relying on the `node.kubeconfig` generated by bootstrapping would never use a rotated cert.  The initial bootstrap certificate is now generated into the cert directory as a PEM file and symlinked to `kubelet-client-current.pem` so that the generated kubeconfig remains valid after rotation. ([#62152](https://gi...

- Reduced memory utilization of admission webhook metrics by removing resource related labels. ([#69895](https://github.com/kubernetes/kubernetes/pull/69895), [@jpbetz](https://github.com/jpbetz))
- Kubelet can now parse PEM file containing both TLS certificate and key in arbitrary order. Previously key was always required to be first. ([#69536](https://github.com/kubernetes/kubernetes/pull/69536), [@awly](https://github.com/awly))

- Kubeadm: tolerate whitespace when validating certificate authority PEM data in kubeconfig files ([#86705](https://github.com/kubernetes/kubernetes/pull/86705), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

- Updated the control plane's trust anchor publisher to create and manage a new ClusterTrustBundle object, associated with the `kubernetes.io/kube-apiserver-serving` X.509 certificate signer. This ClusterTrustBundle contains a PEM bundle in its payload that you can use to verify kube-apiserver serving certificates. ([#127326](https://github.com/kubernetes/kubernetes/pull/127326), [@stlaz](https://github.com/stlaz)) [SIG API Machinery, Apps, Auth, Cluster Lifecycle and Testing]...