loadRevisions example

  protected function revisionOverview(RevisionableInterface $entity): array {
    $build['entity_revisions_table'] = [
      '#theme' => 'table',
      '#header' => [
        'revision' => ['data' => $this->t('Revision')],
        'operations' => ['data' => $this->t('Operations')],
      ],
    ];

    foreach ($this->loadRevisions($entity) as $revision) {
      $build['entity_revisions_table']['#rows'][$revision->getRevisionId()] = $this->buildRow($revision);
    }

    (new CacheableMetadata())
      // Only dealing with this entity and no external dependencies.       ->addCacheableDependency($entity)
      ->addCacheContexts(['languages:language_content'])
      ->applyTo($build);

    return $build;
  }