$form['content_link'] = [
    '#type' => 'container',
    '#parents' => ['content_link_wrapper'],
    '#weight' => -3,
    'widget' => [
      '#title' => t('Content Link'),
      '#description' => t('The content to be linked in the menu.'),
      '#field_name' => 'content_link',
      '#field_parents' => [],
      '#required' => TRUE,
      '#parents' => ['content_link'],
      '#tree' => TRUE,
      '#id' => 'edit-content-link',
      '#type' => 'details',
      '#open' => TRUE,
      'target_id' => [
        '#type' => 'hidden',
        '#id' => 'edit-content-link-target-id',
        '#attributes' => [
          'id' => 'edit-content-link-target-id',
        ],
        '#default_value' => "",
        '#ajax' => [
          'callback' => [
            'Drupalentity_browserPluginFieldFieldWidgetEntityReferenceBrowserWidget',
            'updateWidgetCallback',
          ],
          'wrapper' => 'edit-content-link',
          'event' => 'entity_browser_value_updated',
        ],
      ],
      'entity_browser' => [
        '#type' => 'entity_browser',
        '#entity_browser' => 'image_browser_dropzonejs',
        '#cardinality' => 1,
        '#selection_mode' => 'selection_append',
        '#default_value' => [],
        '#custom_hidden_id' => 'edit-content-link-target-id',
        '#process' => [
          [
            'Drupalentity_browserElementEntityBrowserElement','processEntityBrowser'
          ],
        ],
      ],
      'current' => [
        '#theme_wrappers' => ['container'],
        '#attributes' => [
          'class' => 'entities-list',
        ],
        'items' => [],
      ],
      '#attached' => [
        'library' => [
          'entity_browser/entity_reference',
        ],
      ],
    ],
  ];