- Added a "reason" field to the "image_garbage_collected_total" metric, allowing administrators to differentiate between images that were collected for reasons "age" vs "space".
   ([#123345](https://github.com/kubernetes/kubernetes/pull/123345), [@haircommander](https://github.com/haircommander))

* Allow remote admission controllers to be dynamically added and removed by administrators.  External admission controllers make an HTTP POST containing details of the requested action which the service can approve or reject. ([#46388](https://github.com/kubernetes/kubernetes/pull/46388), [@lavalamp](https://github.com/lavalamp))

  previous releases. When this happens, a `LifecycleHTTPFallback` event is recorded
  in the namespace of the pod and a `kubelet_lifecycle_handler_http_fallbacks_total`
  metric in the kubelet is incremented. Cluster administrators can opt out of the
  expanded lifecycle handler capabilities by setting
  `--feature-gates=ConsistentHTTPGetHandlers=false` in `kubelet`.'

that are visible to `kubectl` users and API consumers, and metrics visible to cluster administrators.
Requests to a deprecated API are returned with a warning containing a target removal release and any replacement API.