- Kubectl [get and describe](https://github.com/kubernetes/enhancements/issues/515) now works with extensions
- Nodes now support [third party monitoring plugins](https://github.com/kubernetes/enhancements/issues/606).

* `kubectl auth reconcile` only works with rbac.v1; all the core helpers have been switched over to use the external types. ([#63967](https://github.com/kubernetes/kubernetes/pull/63967), [@deads2k](https://github.com/deads2k))

hex_digit     = "0" … "9" | "A" … "F" | "a" … "f" .
</pre>

<h2 id="Lexical_elements">Lexical elements</h2>

<h3 id="Comments">Comments</h3>

<p>
Comments serve as program documentation. There are two forms:
</p>

<ol>
<li>
<i>Line comments</i> start with the character sequence <code>//</code>
and stop at the end of the line.
</li>
<li>

   * Glob patterns must be unique, if there's a clash assign to the most
     popular format
   * The main mime type should be the canonical one, use aliases for any
     other widely used forms
   * Where there's a hierarchy in the types, list it via a parent
   * Highly specific magic matches get a high priority
   * General magic matches which could trigger a false-positive need
     a low one

* **[alpha]** New Bootstrap Token authentication and management method. Works well with kubeadm. kubeadm now supports managing tokens, including time based expiration, after the cluster is launched.  See [kubeadm reference docs](https://kubernetes.io/docs/admin/kubeadm/#manage-tokens) for details.

- `kubectl create secret tls` can now read certificate and key files from process substitution arguments ([#67713](https://github.com/kubernetes/kubernetes/pull/67713), [@liggitt](https://github.com/liggitt))
- `kubectl rollout status` now works for unlimited timeouts. ([#67817](https://github.com/kubernetes/kubernetes/pull/67817), [@tnozicka](https://github.com/tnozicka))

### SIG Cloud Provider

* fix WaitForAttach failure issue for azure disk ([#62612](https://github.com/kubernetes/kubernetes/pull/62612), [@andyzhangx](https://github.com/andyzhangx))
* Pod affinity `nodeSelectorTerm.matchExpressions` may now be empty, and works as previously documented: nil or empty `matchExpressions` matches no objects in scheduler. ([#62448](https://github.com/kubernetes/kubernetes/pull/62448), [@k82cn](https://github.com/k82cn))

- `watch.Until` now works for long durations. ([#67350](https://github.com/kubernetes/kubernetes/pull/67350), [@tnozicka](https://github.com/tnozicka))

- Kubectl: --resource-version now works properly in label/annotate/set selector commands when racing with other clients to update the target object ([#85285](https://github.com/kubernetes/kubernetes/pull/85285), [@liggitt](https://github.com/liggitt))

- Enabled kube-controller-manager '--concurrent-job-syncs' flag works on orphan Pod processors ([#126567](https://github.com/kubernetes/kubernetes/pull/126567), [@fusida](https://github.com/fusida)) [SIG Apps]