Set<Feature<?>> features = copyToSet(getFeatures());
    @SuppressWarnings("rawtypes") // class literals
    List<Class<? extends AbstractTester>> testers = getTesters();

    logger.fine(" Testing: " + name);

    // Split out all the specified sizes.
    Set<Feature<?>> sizesToTest = Helpers.copyToSet(CollectionSize.values());
    sizesToTest.retainAll(features);
    features.removeAll(sizesToTest);

- Enable the feature gate `RestartAllContainersOnContainerExits` by default. The RestartAllContainersOnContainerExits feature is promoted to beta. ([#136681](https://github.com/kubernetes/kubernetes/pull/136681), [@yuanwang04](https://github.com/yuanwang04)) [SIG Node and Testing]
- Enables Prometheus native histogram support in apiserver when feature gate is enabled.

- Graduated the `WinDSR` feature in the kube-proxy to beta. The `WinDSR` feature gate is now enabled by default. ([#130876](https://github.com/kubernetes/kubernetes/pull/130876), [@rzlink](https://github.com/rzlink)) [SIG Windows]
- Graduated the asynchronous preemption feature in the scheduler to beta. 

  /**
   * For documenting collections that support no optional features, such as {@link
   * java.util.Collections#emptySet}
   */
  NONE;

  private final Set<Feature<? super Collection>> implied;

  CollectionFeature(Feature<? super Collection>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override
  public Set<Feature<? super Collection>> getImpliedFeatures() {
    return implied;
  }

@GwtCompatible
public class ConflictingRequirementsException extends Exception {
  private final Set<Feature<?>> conflicts;
  private final Object source;

  public ConflictingRequirementsException(
      String message, Set<Feature<?>> conflicts, Object source) {
    super(message);
    this.conflicts = conflicts;
    this.source = source;
  }

  public Set<Feature<?>> getConflicts() {
    return conflicts;
  }

  public Object getSource() {

    List<Feature<?>> features = new ArrayList<>();
    features.add(NoRecurse.SUBMAP);
    features.addAll(parentBuilder.getFeatures());

    return newBuilderUsing(delegate, to, from)
        .named(parentBuilder.getName() + " subMap " + from + "-" + to)
        .withFeatures(features)
        .suppressing(parentBuilder.getSuppressedTests())

import com.google.common.collect.testing.TestListGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.ListFeature;
import java.util.Collections;
import java.util.EnumSet;
import java.util.List;
import java.util.Map.Entry;

    List<Feature<?>> features = new ArrayList<>();
    features.add(NoRecurse.SUBMAP);
    features.addAll(parentBuilder.getFeatures());

    return newBuilderUsing(delegate, to, from)
        .named(parentBuilder.getName() + " subMap " + from + "-" + to)
        .withFeatures(features)
        .suppressing(parentBuilder.getSuppressedTests())

   * but one.
   */
  REJECTS_DUPLICATES_AT_CREATION,

  GENERAL_PURPOSE(SUPPORTS_PUT, SUPPORTS_REMOVE);

  private final Set<Feature<? super Map>> implied;

  MapFeature(Feature<? super Map>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override
  public Set<Feature<? super Map>> getImpliedFeatures() {
    return implied;
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited
  @TesterAnnotation

### Feature

- Feature gates for PortForward (kubectl port-forward) over WebSockets are now enabled by default (Beta).
  - Server-side feature gate: PortForwardWebsocket
  - Client-side (kubectl) feature gate: PORT_FORWARD_WEBSOCKETS environment variable