containers](https://kubernetes.io/docs/concepts/workloads/pods/ephemeral-containers/), it became more obvious how we can support developers with tooling built on top of `kubectl exec`. The addition of the `kubectl debug` [command](https://github.com/kubernetes/enhancements/blob/master/keps/sig-cli/1441-kubectl-debug/README.md) (it is alpha but your feedback is more than welcome), allows developers to easily debug their Pods inside the cluster. We think this addition is invaluable.  This command allows one to create...

## Changelog since v1.27.0

## Urgent Upgrade Notes 

### (No, really, you MUST read this before you upgrade)

- Action required for the custom scheduler plugin developers. 
  Here's the breaking change in `EnqueueExtension` in the scheduling framework. 

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    * Added exported env vars to kubectl plugins so that plugin developers have access to global flags, namespace, the plugin descriptor and the full path to the caller binary.

# OSX leaves these everywhere on SMB shares
._*

# OSX trash
.DS_Store

# Developers can store local stuff in dirs named __something
__*

# Eclipse files
.classpath
.project
.settings/**

# Files generated by JetBrains IDEs, e.g. IntelliJ IDEA
.idea/
*.iml

# Vscode files
.vscode

# This is where the result of the go build goes
/output*/
/_output*/
/_output

# Emacs save files
*~
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   ([#122729](https://github.com/kubernetes/kubernetes/pull/122729), [@jparrill](https://github.com/jparrill))

      * Added exported env vars to kubectl plugins so that plugin developers have access to global flags, namespace, the plugin descriptor and the full path to the caller binary.

  * Enhancement

* MESOS: forward globally declared cadvisor housekeeping flags ([#22974](https://github.com/kubernetes/kubernetes/pull/22974), [@jdef](https://github.com/jdef))
* Trusty: support developer workflow on base image ([#22960](https://github.com/kubernetes/kubernetes/pull/22960), [@andyzheng0831](https://github.com/andyzheng0831))



# v1.2.0

* MESOS: forward globally declared cadvisor housekeeping flags ([#22974](https://github.com/kubernetes/kubernetes/pull/22974), [@jdef](https://github.com/jdef))
* Trusty: support developer workflow on base image ([#22960](https://github.com/kubernetes/kubernetes/pull/22960), [@andyzheng0831](https://github.com/andyzheng0831))

Pruning is activated by setting `spec.preserveUnknownFields: false` in the CustomResourceDefinition. A future apiextensions.k8s.io/v1 variant of CRDs will enforce pruning.