- Client-go certificate manager rotation gained the ability to preserve optional intermediate chains accompanying issued certificates ([#88744](https://github.com/kubernetes/kubernetes/pull/88744), [@jackkleeman](https://github.com/jackkleeman)) [SIG API Machinery and Auth]

  * You can remove the "old" taints (stored internally as annotations) at any time after the upgrade by doing `kubectl annotate nodes <node name> scheduler.alpha.kubernetes.io/taints-` (note the minus at the...

    ([docs](http://kubernetes.io/docs/user-guide/federation/federated-secrets.md))
    ([kubernetes/features#68](https://github.com/kubernetes/enhancements/issues/68))
  - [beta] Federation API server gained support for events and many
    federation controllers now report important events.
    ([docs](http://kubernetes.io/docs/user-guide/federation/events))

  * Fluentd now tolerates all NoExecute Taints when run in gcp configuration. ([#45715](https://github.com/kubernetes/kubernetes/pull/45715), [@gmarek](https://github.com/gmarek))

	* Taints support in gce/salt startup scripts. ([#47632](https://github.com/kubernetes/kubernetes/pull/47632), [@mwielgus](https://github.com/mwielgus))

- A new `TaintNodesByCondition` admission plugin taints newly created Node objects as "not ready", to fix a race condition that could cause pods to be scheduled on new nodes before their taints were updated to accurately reflect their reported conditions. This admission plugin is enabled by default if the `TaintNodesByCondition` feature is enabled. ([#73097](https://gi...

- Kube-scheduler: added taints filtering logic consistent with `TaintToleration` plugin for `PodTopologySpread` plugin. ([#112357](https://github.com/kubernetes/kubernetes/pull/112357), [@SataQiu](https://github.com/SataQiu))

* Add support for running GCI on the GCE cloud provider ([#25425](https://github.com/kubernetes/kubernetes/pull/25425), [@andyzheng0831](https://github.com/andyzheng0831))
* Implement taints and tolerations ([#24134](https://github.com/kubernetes/kubernetes/pull/24134), [@kevin-wangzefeng](https://github.com/kevin-wangzefeng))

- `ValidatingAdmissionPolicy` now preserves types of composition variables, and raises type-related errors early. ([#121001](https://github.com/kubernetes/kubernetes/pull/121001), [@jiahuif](https://github.com/jiahuif))