diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/Field/FieldFormatter/CommentDefaultFormatter.php b/core/modules/comment/lib/Drupal/comment/Plugin/Field/FieldFormatter/CommentDefaultFormatter.php
index bcdf86f..62df554 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/Field/FieldFormatter/CommentDefaultFormatter.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/Field/FieldFormatter/CommentDefaultFormatter.php
@@ -130,13 +130,13 @@ public function viewElements(FieldItemListInterface $items) {
         $this->currentUser->hasPermission('administer comments'))) {
         $mode = $comment_settings['default_mode'];
         $comments_per_page = $comment_settings['per_page'];
-        if ($cids = comment_get_thread($entity, $field_name, $mode, $comments_per_page, $this->settings['pager_id'])) {
+        if ($cids = comment_get_thread($entity, $field_name, $mode, $comments_per_page, $this->getSetting('pager_id'))) {
           $comments = $this->storageController->loadMultiple($cids);
           comment_prepare_thread($comments);
           $build = $this->viewBuilder->viewMultiple($comments);
           $build['pager']['#theme'] = 'pager';
-          if (!empty($this->settings['pager_id'])) {
-            $build['pager']['#element'] = $this->settings['pager_id'];
+          if ($this->getSetting('pager_id')) {
+            $build['pager']['#element'] = $this->getSetting('pager_id');
           }
           $output['comments'] = $build;
         }
diff --git a/core/modules/entity/lib/Drupal/entity/EntityDisplayBase.php b/core/modules/entity/lib/Drupal/entity/EntityDisplayBase.php
index 4ec4313..958084d 100644
--- a/core/modules/entity/lib/Drupal/entity/EntityDisplayBase.php
+++ b/core/modules/entity/lib/Drupal/entity/EntityDisplayBase.php
@@ -85,7 +85,7 @@
    */
   public $originalMode;
 
-  /*
+  /**
    * The renderer objects used for this display, keyed by component name.
    */
   protected $renderers = array();
@@ -98,7 +98,7 @@
   protected $handlerManager;
 
   /**
-   * Context in which this entity will be used (e.g. 'display', 'form').
+   * Context in which this entity will be used (e.g. 'view', 'form').
    *
    * @var string
    */
@@ -239,10 +239,14 @@ public function setComponent($name, array $options = array()) {
 
     // Massage in some values
     $handler = $this->getComponentHandlerByElementName($name);
-    $options = $handler->massageIn($name, $options);
+    if ($handler) {
+      // @todo sometimes handler not found.
+      $options = $handler->massageIn($name, $options);
+    }
 
     $this->content[$name] = $options;
     unset($this->hidden[$name]);
+    unset($this->renderers[$name]);
 
     return $this;
   }
@@ -277,7 +281,12 @@ public function getHighestWeight() {
   }
 
   /**
-   * {@inheritdoc}
+   * Finds component handler by element name.
+   *
+   * @param string $name
+   *   The element name.
+   *
+   * @return \Drupal\entity\Plugin\Type\DisplayComponentHandlerBase
    */
   public function getComponentHandlerByElementName($name) {
     if (!isset($this->handlers[$name])) {
@@ -295,7 +304,12 @@ public function getComponentHandlerByElementName($name) {
     return $this->handlers[$name];
   }
   /**
-   * {@inheritdoc}
+   * Instantiates component handler.
+   *
+   * @param string $type
+   *   The type of component handler (field, extra_field).
+   *
+   * @return \Drupal\entity\Plugin\Type\DisplayComponentHandlerBase
    */
   public function getComponentHandler($type) {
     $handler = $this->handlerManager->getInstance(array('type' => $type));
diff --git a/core/modules/entity/lib/Drupal/entity/Plugin/DisplayComponent/ExtraFieldDisplayComponentHandler.php b/core/modules/entity/lib/Drupal/entity/Plugin/DisplayComponent/ExtraFieldDisplayComponentHandler.php
index ce661f7..799c6cb 100644
--- a/core/modules/entity/lib/Drupal/entity/Plugin/DisplayComponent/ExtraFieldDisplayComponentHandler.php
+++ b/core/modules/entity/lib/Drupal/entity/Plugin/DisplayComponent/ExtraFieldDisplayComponentHandler.php
@@ -46,4 +46,5 @@ public function hasElement($name) {
     $extra_fields = field_info_extra_fields($this->context['entity_type'], $this->context['bundle'], ($this->context['display_context'] == 'view' ? 'display' : $this->context['display_context']));
     return isset($extra_fields[$name]);
   }
+
 }
diff --git a/core/modules/field/lib/Drupal/field/Plugin/DisplayComponent/FieldDisplayComponentHandler.php b/core/modules/field/lib/Drupal/field/Plugin/DisplayComponent/FieldDisplayComponentHandler.php
index 6a9bdc5..65cf61f 100644
--- a/core/modules/field/lib/Drupal/field/Plugin/DisplayComponent/FieldDisplayComponentHandler.php
+++ b/core/modules/field/lib/Drupal/field/Plugin/DisplayComponent/FieldDisplayComponentHandler.php
@@ -96,7 +96,7 @@ public function massageIn($name, array $options = array()) {
       // The field in process of removal from display.
       return $options;
     }
-    if ($this->context['display_context'] == 'display') {
+    if ($this->context['display_context'] == 'view') {
       return $this->formatterPluginManager->prepareConfiguration($field_definition->getType(), $options);
     }
     else {
@@ -124,7 +124,7 @@ public function massageOut($properties) {
    * {@inheritdoc}
    */
   public function prepareDisplayComponents(array &$components, array &$hidden_components) {
-    if ($this->context['display_context'] == 'display') {
+    if ($this->context['display_context'] == 'view') {
       $plugin_manager = $this->formatterPluginManager;
     }
     else {
@@ -190,13 +190,8 @@ public function hasElement($name) {
    * Returns the field definition of a field.
    */
   protected function getFieldDefinition($field_name) {
-    if (isset($definitions[$field_name])) {
-      return $definitions[$field_name];
-    }
-    else {
-      $definitions = $this->getFieldDefinitions();
-      return isset($definitions[$field_name]) ? $definitions[$field_name] : NULL;
-    }
+    $definitions = $this->getFieldDefinitions();
+    return isset($definitions[$field_name]) ? $definitions[$field_name] : NULL;
   }
 
   /**
@@ -226,4 +221,5 @@ protected function getFieldDefinitions() {
 
     return $this->fieldDefinitions;
   }
+
 }