diff --git a/core/modules/config_translation/src/Form/ConfigTranslationFormBase.php b/core/modules/config_translation/src/Form/ConfigTranslationFormBase.php
index 699742d..585264c 100644
--- a/core/modules/config_translation/src/Form/ConfigTranslationFormBase.php
+++ b/core/modules/config_translation/src/Form/ConfigTranslationFormBase.php
@@ -166,10 +166,10 @@ public function buildForm(array $form, FormStateInterface $form_state, Request $
 
     $form['#attached']['library'][] = 'config_translation/drupal.config_translation.admin';
 
-    $form['config_names'] = array(
-      '#type' => 'container',
-      '#tree' => TRUE,
-    );
+    // Even though this is a nested form, we do not set #tree to TRUE because
+    // the form value structure is generated by using #parents for each element.
+    // @see \Drupal\config_translation\FormElement\FormElementBase::getElements()
+    $form['config_names'] = array('#type' => 'container');
     foreach ($this->mapper->getConfigNames() as $name) {
       $form['config_names'][$name] = array('#type' => 'container');
       $form['config_names'][$name] += $this->buildConfigForm($name, $this->typedConfigManager->get($name), $this->baseConfigData[$name], $config_factory->get($name)->get());
@@ -256,16 +256,7 @@ protected function buildConfigForm($name, ArrayElement $schema, $source_config,
 
     if ($form_element = $this->createFormElement($schema)) {
       $parents = array('config_names', $name);
-      $key = '';
-      $build = $form_element->getElements($this->sourceLanguage, $this->language, $source_config, $translation_config, $key, $parents);
-    }
-    else {
-      $definition = $schema->getDefinition();
-      $this->logger('config_translation')->notice("No form element class exists for config schema definition '@name'", array('@name', $definition->getLabel()));
-    }
-
-    if ($build) {
-      $build[$key]['#open'] = TRUE;
+      $build = $form_element->getElements($this->sourceLanguage, $this->language, $source_config, $translation_config, $parents);
     }
 
     return $build;
@@ -277,19 +268,19 @@ protected function buildConfigForm($name, ArrayElement $schema, $source_config,
    * @param \Drupal\Core\TypedData\TypedDataInterface $schema
    *   Schema definition of configuration.
    *
-   * @return \Drupal\config_translation\FormElement\ElementInterface|NULL
+   * @return \Drupal\config_translation\FormElement\ElementInterface|null
    *   The element builder object if possible.
    */
   public static function createFormElement(TypedDataInterface $schema) {
     $definition = $schema->getDataDefinition();
-    if (!empty($definition['translatable']) || $schema instanceof ArrayElement) {
+    // Form element classes can be specified even for non-translatable elements
+    // such as the ListElement form element which used for for Mapping and List
+    // schema elements.
+    if (isset($definition['form_element_class'])) {
       if (!$definition->getLabel()) {
         $definition->setLabel(t('n/a'));
       }
-      if (isset($definition['form_element_class'])) {
-        /** @var \Drupal\config_translation\FormElement\ElementInterface $form_element */
-        return new $definition['form_element_class']($schema);
-      }
+      return new $definition['form_element_class']($schema);
     }
   }
 
diff --git a/core/modules/config_translation/src/FormElement/DateFormat.php b/core/modules/config_translation/src/FormElement/DateFormat.php
index 49e0c12..729afee 100644
--- a/core/modules/config_translation/src/FormElement/DateFormat.php
+++ b/core/modules/config_translation/src/FormElement/DateFormat.php
@@ -27,7 +27,6 @@ public function getTranslationElement(LanguageInterface $translation_language, $
 
     return array(
       '#type' => 'textfield',
-      '#title' => $this->t($definition->getLabel()) . '<span class="visually-hidden"> (' . $language->name . ')</span>',
       '#description' => $description,
       '#field_suffix' => ' <div class="edit-date-format-suffix"><small id="edit-date-format-suffix">' . $format . '</small></div>',
       '#ajax' => array(
diff --git a/core/modules/config_translation/src/FormElement/ElementInterface.php b/core/modules/config_translation/src/FormElement/ElementInterface.php
index 47cd387..d0df738 100644
--- a/core/modules/config_translation/src/FormElement/ElementInterface.php
+++ b/core/modules/config_translation/src/FormElement/ElementInterface.php
@@ -28,15 +28,16 @@
    *   The configuration value of the element in the source language.
    * @param mixed $translation_config
    *   The configuration value of the element in the language to translate to.
-   * @param string $base_key
-   *   Base key to be used for the elements in the form.
    * @param array $parents
    *   Parents array for the element in the form.
+   * @param string $base_key
+   *   (optional) Base key to be used for the elements in the form. NULL for
+   *   top-level form elements.
    *
    * @return array
    *   A render array for the source value.
    */
-  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $base_key, $parents);
+  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $parents, $base_key = NULL);
 
   /**
    * Sets configuration based on a nested form value array.
diff --git a/core/modules/config_translation/src/FormElement/FormElementBase.php b/core/modules/config_translation/src/FormElement/FormElementBase.php
index 3881346..9caa7f7 100644
--- a/core/modules/config_translation/src/FormElement/FormElementBase.php
+++ b/core/modules/config_translation/src/FormElement/FormElementBase.php
@@ -50,8 +50,8 @@ public function __construct(TypedDataInterface $element) {
   /**
    * {@inheritdoc}
    */
-  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $base_key, $parents) {
-    $build[$base_key]['#theme'] = 'config_translation_manage_form_element';
+  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $parents, $base_key = NULL) {
+    $build['#theme'] = 'config_translation_manage_form_element';
 
     // For accessibility we make source and translation appear next to each
     // other in the source for each element, which is why we utilize the
@@ -61,11 +61,11 @@ public function getElements(LanguageInterface $source_language, LanguageInterfac
     // configuration values in ConfigTranslationFormBase::setConfig().
     // Therefore we make the 'source' and 'translation' keys the top-level
     // keys in $form_state['values'].
-    $build[$base_key]['source'] = $this->getSourceElement($source_language, $source_config);
-    $build[$base_key]['translation'] = $this->getTranslationElement($translation_language, $source_config, $translation_config);
+    $build['source'] = $this->getSourceElement($source_language, $source_config);
+    $build['translation'] = $this->getTranslationElement($translation_language, $source_config, $translation_config);
 
-    $build[$base_key]['source']['#parents'] = array_merge(array('source'), $parents);
-    $build[$base_key]['translation']['#parents'] = array_merge(array('translation'), $parents);
+    $build['source']['#parents'] = array_merge(array('source'), $parents);
+    $build['translation']['#parents'] = array_merge(array('translation'), $parents);
     return $build;
   }
 
diff --git a/core/modules/config_translation/src/FormElement/ListElement.php b/core/modules/config_translation/src/FormElement/ListElement.php
index 0314a3c..18c0687 100644
--- a/core/modules/config_translation/src/FormElement/ListElement.php
+++ b/core/modules/config_translation/src/FormElement/ListElement.php
@@ -8,17 +8,19 @@
 namespace Drupal\config_translation\FormElement;
 
 use Drupal\Core\Config\Config;
-use Drupal\Core\Config\Schema\Element;
 use Drupal\Core\Language\LanguageInterface;
 use Drupal\Core\Config\Schema\ArrayElement;
 use Drupal\config_translation\Form\ConfigTranslationFormBase;
-use Drupal\Core\TypedData\TypedDataInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Drupal\Core\TypedData\DataDefinitionInterface;
 use Drupal\language\Config\LanguageConfigOverride;
 
 /**
  * Defines the list element for the configuration translation interface.
  */
-class ListElement extends FormElementBase {
+class ListElement implements ElementInterface {
+
+  use StringTranslationTrait;
 
   /**
    * The schema element this form is for.
@@ -28,19 +30,27 @@ class ListElement extends FormElementBase {
   protected $element;
 
   /**
+   * The data definition of the element this form element is for.
+   *
+   * @var \Drupal\Core\TypedData\ListDataDefinitionInterface
+   */
+  protected $definition;
+
+  /**
    * Constructs a FormElementBase.
    *
    * @param \Drupal\Core\Config\Schema\ArrayElement $element
    *   The schema element this form element is for.
    */
   public function __construct(ArrayElement $element) {
-    parent::__construct($element);
+    $this->element = $element;
+    $this->definition = $element->getDataDefinition();
   }
 
   /**
    * {@inheritdoc}
    */
-  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $base_key, $parents) {
+  public function getElements(LanguageInterface $source_language, LanguageInterface $translation_language, $source_config, $translation_config, $parents, $base_key = NULL) {
     $build = array();
     foreach ($this->element as $key => $element) {
       $sub_build = array();
@@ -67,39 +77,23 @@ public function getElements(LanguageInterface $source_language, LanguageInterfac
         // Therefore we make the 'source' and 'translation' keys the top-level
         // keys in $form_state['values'].
         $element_parents = array_merge($parents, array($key));
-        $sub_build += $form_element->getElements($source_language, $translation_language, $source_config[$key], $translation_config[$key], $element_key, $element_parents);
+        $sub_build += $form_element->getElements($source_language, $translation_language, $source_config[$key], $translation_config[$key], $element_parents, $element_key);
+
+        if (empty($sub_build)) {
+          continue;
+        }
+
         // Build sub-structure and include it with a wrapper in the form
         // if there are any translatable elements there.
-        if (!empty($sub_build) && $element instanceof ArrayElement) {
-          // For some configuration elements the same element structure can
-          // repeat multiple times, (like views displays, filters, etc.).
-          // So try to find a more usable title for the details summary. First
-          // check if there is an element which is called title or label, then
-          // check if there is an element which contains these words.
-          $title = '';
-          if (isset($sub_build['title']['source'])) {
-            $title = $sub_build['title']['source']['#markup'];
-          }
-          elseif (isset($sub_build['label']['source'])) {
-            $title = $sub_build['label']['source']['#markup'];
-          }
-          else {
-            foreach (array_keys($sub_build) as $title_key) {
-              if (isset($sub_build[$title_key]['source']) && (strpos($title_key, 'title') !== FALSE || strpos($title_key, 'label') !== FALSE)) {
-                $title = $sub_build[$title_key]['source']['#markup'];
-                break;
-              }
-            }
-          }
-          $build[$base_key] = array(
+        $build[$key] = array();
+        if ($element instanceof ArrayElement) {
+          $build[$key] = array(
             '#type' => 'details',
-            '#title' => (!empty($title) ? (strip_tags($title) . ' ') : '') . $this->t($definition['label']),
-            '#open' => FALSE,
-          ) + $sub_build;
-        }
-        else {
-          $build += $sub_build;
+            '#title' => $this->getGroupTitle($definition, $sub_build),
+            '#open' => empty($base_key),
+          );
         }
+        $build[$key] += $sub_build;
       }
     }
 
@@ -126,4 +120,41 @@ public function setConfig(Config $base_config, LanguageConfigOverride $config_tr
     }
   }
 
+  /**
+   * Returns the title for the 'details' element of a group of schema elements.
+   *
+   * For some configuration elements the same element structure can be repeated
+   * multiple times (for example views displays, filters, etc.). Thus, we try to
+   * find a more usable title for the details summary. First check if there is
+   * an element which is called title or label and use its value, then check if
+   * there is an element which contains these words and use those. Fall back
+   * to the generic definition label if no such element is found.
+   *
+   * @param \Drupal\Core\TypedData\DataDefinitionInterface $definition
+   *   The defintion of the schema element.
+   * @param $group_build
+   *   The renderable array for the group of schema elements.
+   *
+   * @return string
+   *   The title for the group of schema elements.
+   */
+  protected function getGroupTitle(DataDefinitionInterface $definition, $group_build) {
+    $title = '';
+    if (isset($group_build['title']['source'])) {
+      $title = $group_build['title']['source']['#markup'];
+    }
+    elseif (isset($group_build['label']['source'])) {
+      $title = $group_build['label']['source']['#markup'];
+    }
+    else {
+      foreach (array_keys($group_build) as $title_key) {
+        if (isset($group_build[$title_key]['source']) && (strpos($title_key, 'title') !== FALSE || strpos($title_key, 'label') !== FALSE)) {
+          $title = $group_build[$title_key]['source']['#markup'];
+          break;
+        }
+      }
+    }
+    return (!empty($title) ? (strip_tags($title) . ' ') : '') . $this->t($definition['label']);
+  }
+
 }
diff --git a/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php b/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
index 6c29709..d33a565 100644
--- a/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
+++ b/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
@@ -671,7 +671,7 @@ public function testTextFormatTranslation() {
     $config_factory = $this->container->get('config.factory');
 
     $expected = array(
-      'value' => '<strong>Hello World</strong>',
+      'value' => '<p><strong>Hello World</strong></p>',
       'format' => 'plain_text',
     );
     $actual = $config_factory
@@ -695,7 +695,7 @@ public function testTextFormatTranslation() {
 
     // Update translatable fields.
     $edit = array(
-      'translation[config_names][config_translation_test.content][content][value]' => '<strong>Hello World</strong> - FR',
+      'translation[config_names][config_translation_test.content][content][value]' => '<p><strong>Hello World</strong> - FR</p>',
     );
 
     // Save language specific version of form.
@@ -703,7 +703,7 @@ public function testTextFormatTranslation() {
 
     // Get translation and check we've got the right value.
     $expected = array(
-      'value' => '<strong>Hello World</strong> - FR',
+      'value' => '<p><strong>Hello World</strong> - FR</p>',
       'format' => 'plain_text',
     );
     $this->container->get('language.config_factory_override')
@@ -751,7 +751,7 @@ public function testTextFormatTranslation() {
     );
     $this->drupalPostForm($translation_page_url, $edit, t('Save translation'));
     $expected = array(
-      'value' => '<strong>Hello World</strong> - FR',
+      'value' => '<p><strong>Hello World</strong> - FR</p>',
       'format' => 'full_html',
     );
     $actual = $config_factory