* Websocket requests may now authenticate to the API server by passing a bearer token in a websocket subprotocol of the form `base64url.bearer.authorization.k8s.io.<base64url-encoded-bearer-token>`. ([#47740](https://github.com/kubernetes/kubernetes/pull/47740), [@liggitt](https://github.com/liggitt))

  </mime-type>
  <mime-type type="application/vnd.uplanet.alert"/>
  <mime-type type="application/vnd.uplanet.alert-wbxml"/>
  <mime-type type="application/vnd.uplanet.bearer-choice"/>
  <mime-type type="application/vnd.uplanet.bearer-choice-wbxml"/>
  <mime-type type="application/vnd.uplanet.cacheop"/>
  <mime-type type="application/vnd.uplanet.cacheop-wbxml"/>
  <mime-type type="application/vnd.uplanet.channel"/>

* Added a new secret type "bootstrap.kubernetes.io/token" for dynamically creating TLS bootstrapping bearer tokens. ([#41281](https://github.com/kubernetes/kubernetes/pull/41281), [@ericchiang](https://github.com/ericchiang))

### Service

  must contain '^' or the '//' prefix to anchor to the start, and '$' or the port separator ':' to anchor to 
  the end. ([#112809](https://github.com/kubernetes/kubernetes/pull/112809), [@tkashem](https://github.com/tkashem)) [SIG API Machinery]

- Added an option to enable leader election in local-up-cluster.sh via the LEADER_ELECT CLI flag. ([#127786](https://github.com/kubernetes/kubernetes/pull/127786), [@Jefftree](https://github.com/Jefftree))

pkg html/template, func ParseFS(fs.FS, ...string) (*Template, error)
pkg html/template, method (*Template) ParseFS(fs.FS, ...string) (*Template, error)
pkg io, func NopCloser(Reader) ReadCloser
pkg io, func ReadAll(Reader) ([]uint8, error)
pkg io, type ReadSeekCloser interface { Close, Read, Seek }
pkg io, type ReadSeekCloser interface, Close() error
pkg io, type ReadSeekCloser interface, Read([]uint8) (int, error)

request alternate representations of normal Kubernetes objects by passing an `Accept` header like `application/json;as=Table;g=meta.k8s.io;v=v1beta1` or `application/json;as=PartialObjectMetadata;g=meta.k8s.io;v1=v1beta1`.  Older servers will ignore this representation or return an error if it is not available.  Clients may request fallback to the normal object by adding a non-qualified mime-type to their `Accept` header like `application/json` - the server will then respond with either the alternate...

pkg net/http, const StatusEarlyHints = 103
pkg net/http, const StatusEarlyHints ideal-int
pkg net/http, func NewRequestWithContext(context.Context, string, string, io.Reader) (*Request, error)
pkg net/http, method (Header) Clone() Header
pkg net/http, method (*Request) Clone(context.Context) *Request
pkg net/http, method (*Transport) Clone() *Transport

- The deprecated flag `--lock-object-namespace` and `--lock-object-name` have been removed from kube-scheduler. Please use `--leader-elect-resource-namespace` and `--leader-elect-resource-name` or ComponentConfig instead to configure those parameters. ([#119130](https://github.com/kubernetes/kubernetes/pull/119130), [@SataQiu](https://github.com/SataQiu)) [SIG Scheduling]

* Use separate client for leader election in scheduler to avoid starving leader election by regular scheduler operations. ([#53793](https://github.com/kubernetes/kubernetes/pull/53793), [@wojtek-t](https://github.com/wojtek-t))