The API Server will no longer proxy non-101 responses for upgrade requests. This could break proxied backends (such as an extension API server) that respond to upgrade requests with a non-101 response code. ([#92941](https://github.com/kubernetes/kubernetes/pull/92941), [@tallclair](https://github.com/tallclair)) [SIG API Machinery]

	// 3.1 Execute the request.
	resp, err := s.TestSuiteCommon.client.Do(req)
	if err != nil {
		c.Fatalf("unexpected request err: %v", err)
	}
	if resp.StatusCode != 200 {
		c.Fatalf("got unexpected response: %#v\n", resp)
	}

	// 3.2 check that user cannot delete the bucket
	err = uClient.RemoveBucket(ctx, bucket)
	if err == nil || err.Error() != "Access Denied." {

  The API Server will no longer proxy non-101 responses for upgrade requests. This could break proxied backends (such as an extension API server) that respond to upgrade requests with a non-101 response code. ([#92941](https://github.com/kubernetes/kubernetes/pull/92941), [@tallclair](https://github.com/tallclair)) [SIG API Machinery]
 
## Changes by Kind

- Resolves a spurious "Unknown discovery response content-type" error in client-go discovery requests by tolerating extra content-type parameters in API responses ([#117571](https://github.com/kubernetes/kubernetes/pull/117571), [@seans3](https://github.com/seans3)) [SIG API Machinery]

  The API Server will no longer proxy non-101 responses for upgrade requests. This could break proxied backends (such as an extension API server) that respond to upgrade requests with a non-101 response code. ([#92941](https://github.com/kubernetes/kubernetes/pull/92941), [@tallclair](https://github.com/tallclair)) [SIG API Machinery]
 
## Changes by Kind

onseHeader","getAllResponseHeaders","setRequestHeader","overrideMimeType","mimeType","status","abort","statusText","finalText","crossDomain","host","hasContent","ifModified","headers","beforeSend","success","send","nativeStatusText","responses","isSuccess","response","modified","ct","finalDataType","firstDataType","ajaxHandleResponses","conv2","current","conv","dataFilter","throws","ajaxConvert","getJSON","getScript","text script","wrapAll","firstElementChild","wrapInner","htmlIsFunction","unwra...

- Kube-apiserver: redirect responses are no longer returned from backends by default. Set `--aggregator-reject-forwarding-redirect=false` to continue forwarding redirect responses. ([#112330](https://github.com/kubernetes/kubernetes/pull/112330), [@enj](https://github.com/enj)) [SIG API Machinery]

## Dependencies

### Added

- Added `apiserver_watch_list_duration_seconds` metrics which will measure response latency distribution in seconds for watchlist requests broken by group, version, resource and scope. ([#120490](https://github.com/kubernetes/kubernetes/pull/120490), [@p0lyn0mial](https://github.com/p0lyn0mial))

```

Check if event notification is successfully configured by

```
mc event list myminio/images
```

You should get a response like this

```
arn:minio:sqs::1:webhook   s3:ObjectCreated:*   Filter: suffix=".jpg"
```

### Step 3: Test with Thumbnailer

- Kube-apiserver: redirect responses are no longer returned from backends by default. Set `--aggregator-reject-forwarding-redirect=false` to continue forwarding redirect responses. ([#112359](https://github.com/kubernetes/kubernetes/pull/112359), [@enj](https://github.com/enj)) [SIG API Machinery]