reverted:
--- b/core/modules/contact/lib/Drupal/contact/CategoryListController.php
+++ a/core/modules/contact/lib/Drupal/contact/CategoryListController.php
@@ -1,81 +1,21 @@
 <?php
 
 /**
+ * Definition of Drupal\contact\CategoryListController.
- * Contains \Drupal\contact\CategoryListController.
  */
 
 namespace Drupal\contact;
 
 use Drupal\Core\Config\Entity\ConfigEntityListController;
 use Drupal\Core\Entity\EntityInterface;
-use Drupal\Core\Form\FormInterface;
-use Drupal\Core\Config\ConfigFactory;
-use Symfony\Component\DependencyInjection\ContainerInterface;
-use Drupal\Core\Extension\ModuleHandlerInterface;
-use Drupal\contact\CategoryStorageController;
-use Drupal\Component\Utility\String;
 
 /**
  * Provides a listing of contact categories.
  */
+class CategoryListController extends ConfigEntityListController {
-class CategoryListController extends ConfigEntityListController implements FormInterface {
 
   /**
+   * Overrides Drupal\Core\Entity\EntityListController::getOperations().
-   * Stores the configuration factory.
-   *
-   * @var \Drupal\Core\Config\ConfigFactory
-   */
-  protected $configFactory;
-
-  /**
-   * Stores the default category.
-   *
-   * @var string
-   */
-  protected $defaultCategory;
-
-  /**
-   * Constructs a new CategoryListController.
-   *
-   * @param string $entity_type
-   *   The type of entity to be listed.
-   * @param array $entity_info
-   *   An array of entity info for the entity type.
-   * @param \Drupal\contact\CategoryStorageController $storage
-   *   The contact category storage controller class.
-   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
-   *   The module handler to invoke hooks on.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
-   *   The factory for configuration objects.
-   */
-  public function __construct($entity_type, array $entity_info, CategoryStorageController $storage, ModuleHandlerInterface $module_handler, ConfigFactory $config_factory) {
-    parent::__construct($entity_type, $entity_info, $storage, $module_handler);
-    $this->configFactory = $config_factory;
-    $this->defaultCategory = $config_factory->get('contact.settings')->get('default_category');
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function createInstance(ContainerInterface $container, $entity_type, array $entity_info) {
-    return new static(
-      $entity_type,
-      $entity_info,
-      $container->get('plugin.manager.entity')->getStorageController($entity_type),
-      $container->get('module_handler'),
-      $container->get('config.factory')
-    );
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getFormID() {
-    return 'contact_category_list_form';
-  }
-
-  /**
-   * {@inheritdoc}
    */
   public function getOperations(EntityInterface $entity) {
     $operations = parent::getOperations($entity);
@@ -104,134 +44,33 @@
   }
 
   /**
+   * Overrides Drupal\Core\Entity\EntityListController::buildHeader().
-   * {@inheritdoc}
    */
   public function buildHeader() {
     $row['category'] = t('Category');
     $row['recipients'] = t('Recipients');
+    $row['selected'] = t('Selected');
-    $row['default'] = t('Default');
     $row['operations'] = t('Operations');
     return $row;
   }
 
   /**
+   * Overrides Drupal\Core\Entity\EntityListController::buildRow().
-   * {@inheritdoc}
    */
   public function buildRow(EntityInterface $entity) {
+    $row['category'] = check_plain($entity->label());
-    $row['category'] = String::checkPlain($entity->label());
     // Special case the personal category.
     if ($entity->id() == 'personal') {
       $row['recipients'] = t('Selected user');
+      $row['selected'] = t('No');
-      $row['default'] = t('No');
     }
     else {
       $row['recipients'] = check_plain(implode(', ', $entity->recipients));
+      $default_category = config('contact.settings')->get('default_category');
+      $row['selected'] = ($default_category == $entity->id() ? t('Yes') : t('No'));
-      $row['default'] = ($this->defaultCategory == $entity->id() ? t('Yes') : t('No'));
     }
     $row['operations']['data'] = $this->buildOperations($entity);
     return $row;
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function render() {
-    $entities = $this->load();
-    if (count($entities) > 1) {
-      // Creates a form for manipulating contact category form weights.
-      return drupal_get_form($this);
-    }
-
-    return parent::render();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function buildForm(array $form, array &$form_state) {
-    $form['entities'] = array(
-      '#type' => 'table',
-      '#header' => $this->buildHeader() + array('weight' => t('Weight')),
-      '#empty' => t('There is no @label yet.', array('@label' => $this->entityInfo['label'])),
-      '#tabledrag' => array(
-        array('order', 'sibling', 'weight'),
-      ),
-    );
-    foreach ($this->load() as $entity) {
-      $row = $this->buildRow($entity);
-      // Override default values to markup elements.
-      $row['category'] = array(
-        '#markup' => $row['category'],
-      );
-      $row['recipients'] = array(
-        '#markup' => $row['recipients'],
-      );
-      // Allow to change default contact category.
-      $row['default'] = array(
-        '#type' => 'radio',
-        '#title' => t('Set @title as default', array('@title' => $entity->label())),
-        '#title_display' => 'invisible',
-        '#return_value' => $entity->id(),
-        '#default_value' => ($this->defaultCategory == $entity->id() ? $entity->id() : NULL),
-        '#parents' => array('default_category'),
-        '#id' => 'edit-entities-default',
-        // Personal category could not be set default.
-        '#access' => $entity->id() != 'personal',
-      );
-      // Add weight column and ordering.
-      $row['#weight'] = $entity->get('weight');
-      $row['#attributes']['class'][] = 'draggable';
-      $row['weight'] = array(
-        '#type' => 'weight',
-        '#title' => t('Weight for @title', array('@title' => $entity->label())),
-        '#title_display' => 'invisible',
-        '#default_value' => $entity->get('weight'),
-        '#attributes' => array('class' => array('weight')),
-      );
-
-      $form['entities'][$entity->id()] = $row;
-    }
-
-    $form['actions']['#type'] = 'actions';
-    $form['actions']['submit'] = array(
-      '#type' => 'submit',
-      '#value' => t('Save changes'),
-      '#button_type' => 'primary',
-    );
-
-    return $form;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function validateForm(array &$form, array &$form_state) {
-    // No validation.
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function submitForm(array &$form, array &$form_state) {
-    $values = $form_state['values']['entities'];
-
-    $entities = $this->storage->loadMultiple(array_keys($values));
-    foreach ($values as $id => $value) {
-      if (isset($entities[$id]) && $value['weight'] != $entities[$id]->get('weight')) {
-        // Update changed weight.
-        $entities[$id]->set('weight', $value['weight']);
-        $entities[$id]->save();
-      }
-    }
-    // Update the site's default contact category.
-    $default_category = $form_state['values']['default_category'];
-    if (isset($entities[$default_category]) && $default_category != $this->defaultCategory) {
-      $this->configFactory->get('contact.settings')
-        ->set('default_category', $default_category)
-        ->save();
-    }
-
-    drupal_set_message(t('Changes have been saved.'));
-  }
-
 }
reverted:
--- b/core/modules/contact/lib/Drupal/contact/Tests/ContactSitewideTest.php
+++ a/core/modules/contact/lib/Drupal/contact/Tests/ContactSitewideTest.php
@@ -222,7 +222,15 @@
     $this->drupalGet('admin/structure/contact');
 
     // Find out in which row the category we want to add a field to is.
+    $i = 0;
+    foreach($this->xpath('//table/tbody/tr') as $row) {
+      if (((string)$row->td[0]) == $label) {
+        break;
+      }
+      $i++;
+    }
+
+    $this->clickLink(t('Manage fields'), $i);
-    $this->drupalGet('admin/structure/contact/manage/' . $category . '/fields');
     $this->assertResponse(200);
 
     // Create a simple textfield.
only in patch2:
unchanged:
--- a/core/modules/contact/src/Tests/ContactSitewideTest.php
+++ b/core/modules/contact/src/Tests/ContactSitewideTest.php
@@ -238,15 +238,7 @@ function testSiteWideContact() {
     $this->drupalGet('admin/structure/contact');
 
     // Find out in which row the category we want to add a field to is.
-    $i = 0;
-    foreach($this->xpath('//table/tbody/tr') as $row) {
-      if (((string)$row->td[0]) == $label) {
-        break;
-      }
-      $i++;
-    }
-
-    $this->clickLink(t('Manage fields'), $i);
+    $this->drupalGet('admin/structure/contact/manage/' . $category . '/fields');
     $this->assertResponse(200);
 
     // Create a simple textfield.