- `kubectl run --env` no longer supports CSV parsing. To provide multiple environment
  variables, use the `--env` flag multiple times instead. Example: `--env ONE=1 --env TWO=2` instead of `--env ONE=1,TWO=2`.

- Removed deprecated command `kubectl stop`.

- Kubectl can now use http caching for the OpenAPI schema. The cache

- Kubenet: added HostPort IPv6 support.  HostPortManager: operates only with one IP family, failing if receives port mapping entries with different IP families.  HostPortSyncer: operates only with one IP family, skipping portmap entries with different IP families ([#80854](https://github.com/kubernetes/kubernetes/pull/80854), [@aojea](https://github.com/aojea))

-->

#### What type of PR is this?

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/kind cleanup
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  - Use of the...

* The old dynamic client has been replaced by a new one.  The previous dynamic client will exist for one release in `client-go/deprecated-dynamic`.  Switch as soon as possible. ([#63446](https://github.com/kubernetes/kubernetes/pull/63446), [@deads2k](https://github.com/deads2k))