Drupal 8 Custom Breadcrumb block printing the 2 top level breadcrumbs including page title

CustomBreadcrumbBlock.php

<?php

namespace Drupal\custom_breadcrumb_block\Plugin\Block;

use Drupal\Core\Block\BlockBase;
use Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\Core\Routing\RouteMatchInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Drupal\Core\Controller\TitleResolverInterface;

/**
 * Provides a 'Breadcrumb' Block.
 *
 * @Block(
 *   id = "custom_breadcrumb_block",
 *   admin_label = @Translation("Custom Breadcrumb block"),
 *   category = @Translation("Custom Blocks"),
 * )
 */
class CustomBreadcrumbBlock extends BlockBase implements ContainerFactoryPluginInterface {


  /**
   * The breadcrumb manager.
   *
   * @var \Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface
   */
  protected $breadcrumbManager;

  /**
   * The current route match.
   *
   * @var \Drupal\Core\Routing\RouteMatchInterface
   */
  protected $routeMatch;

  /**
   * The title resolver service.
   *
   * @var \Drupal\Core\Controller\TitleResolverInterface
   */
  protected $titleResolver;

  /**
   * Constructs a new CustomBreadcrumbBlock object.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param mixed $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface $breadcrumb_manager
   *   The breadcrumb manager.
   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
   *   The current route match.
   * @param \Drupal\Core\Controller\TitleResolverInterface $titleResolver
   *   The title resolver.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, BreadcrumbBuilderInterface $breadcrumb_manager, RouteMatchInterface $route_match, TitleResolverInterface $titleResolver) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->breadcrumbManager = $breadcrumb_manager;
    $this->routeMatch = $route_match;
    $this->titleResolver = $titleResolver;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $configuration,
      $plugin_id,
      $plugin_definition,
      $container->get('breadcrumb'),
      $container->get('current_route_match'),
      $container->get('title_resolver')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function build() {
    $breadcrumbs = $this->breadcrumbManager->build($this->routeMatch)->getLinks();
    $items = [];
    if(!empty($breadcrumbs[1])){
      $items[] = $breadcrumbs[1]->getText();
    }
    if(!empty($breadcrumbs[2])){
      $items[] = $breadcrumbs[2]->getText();
    }
    // Fallback: Page title
    $request = \Drupal::request();
    $page_title =  $this->titleResolver->getTitle($request, $this->routeMatch->getRouteObject());
    if(!empty($page_title)){
      $items[] = $page_title;
    }
    
    return [
      '#type' => 'inline_template',
      '#template' => '
        <div class="custom-markup-block">
          <div class="first">
            {{ linkFirst }}
          </div>
          {% if linkSecond is not empty %}
            <div class="second">
              {{ linkSecond }}
            </div>
          {% endif %}
        </div>',
      '#context' => [
        'linkFirst' => !empty($items[0]) ? $items[0] : NULL,
        'linkSecond' => !empty($items[1]) ? $items[1] : NULL,
      ],
      '#cache' => array(
        'contexts' => array('url.path'),
      ),
    ];
  }

}