* Check for known manifests during preflight instead of only checking for non-empty manifests directory. This makes the preflight checks less heavy-handed by specifically checking for well-known files (kube-apiserver.yaml, kube-controller-manager.yaml, kube-scheduler.yaml, etcd.yaml) in /etc/kubernetes/manifests instead of simply checking for a non-empty directory. ([#57287](https://github.com/kubernetes/kubernetes/pull/57287), [@mattkelly](https://github.com/mattkelly))

* Fix aggressive VM calls for Azure VMSS ([#83102](https://github.com/kubernetes/kubernetes/pull/83102), [@feiskyer](https://github.com/feiskyer))

    * Disable timestamp adjustment in logs to optimize performance.
    * Reduce logging agent buffer chunk limit to 512k to optimize performance.
* Fix a bug on GCE that /etc/crictl.yaml is not generated when crictl is preloaded. ([#66877](https://github.com/kubernetes/kubernetes/pull/66877), [@Random-Liu](https://github.com/Random-Liu))

  repeated KeyToPath items = 2;

  // defaultMode is optional: mode bits used to set permissions on created files by default.
  // Must be an octal value between 0000 and 0777 or a decimal value between 0 and 511.
  // YAML accepts both octal and decimal values, JSON requires decimal values for mode bits.
  // Defaults to 0644.
  // Directories within the path are not affected by this setting.

*   The Kubelet's feature gates are now specified as a map when provided via a JSON or YAML KubeletConfiguration, rather than as a string of key-value pairs, making them less awkward for users. ([#53025](https://github.com/kubernetes/k...

## Changelog since v1.12.0

### Other notable changes

* kubeadm now allows mixing of init/cluster and join configuration in a single YAML file (although a warning gets printed in this case).  ([#69426](https://github.com/kubernetes/kubernetes/pull/69426), [@rosti](https://github.com/rosti))

		* `kubectl version` has new flag --output (=json or yaml) allowing result of the command to be parsed in either json format or yaml. ([#39858](https://github.com/kubernetes/kubernetes/pull/39858), [@alejandroEsc](https://github.com/alejandroEsc))


  * Bug fixes

### Other notable changes

* Fix aggressive VM calls for Azure VMSS ([#83102](https://github.com/kubernetes/kubernetes/pull/83102), [@feiskyer](https://github.com/feiskyer))

- Fix unsafe JSON construction in a number of locations in the codebase ([#81158](https://github.com/kubernetes/kubernetes/pull/81158), [@zouyee](https://github.com/zouyee))

### API Change

- Protobuf serialization of metav1.MicroTime timestamps (used in `Lease` and `Event` API objects) has been corrected to truncate to microsecond precision, to match the documented behavior and JSON/YAML serialization. Any existing persisted data is truncated to microsecond when read from etcd. ([#111936](https://github.com/kubernetes/kubernetes/pull/111936), [@haoruan](https://github.com/haoruan)) [SIG API Machinery]

### Feature