diff --git a/core/modules/comment/comment.install b/core/modules/comment/comment.install
index 391a255..fc859ba 100644
--- a/core/modules/comment/comment.install
+++ b/core/modules/comment/comment.install
@@ -5,6 +5,7 @@
  * Install, update and uninstall functions for the Comment module.
  */
 
+use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\field\Entity\FieldConfig;
 
 /**
@@ -48,7 +49,7 @@ function comment_schema() {
         'type' => 'varchar',
         'not null' => TRUE,
         'default' => 'node',
-        'length' => 255,
+        'length' => EntityTypeInterface::ID_MAX_LENGTH,
         'description' => 'The entity_type of the entity to which this comment is a reply.',
       ),
       'field_name' => array(
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index 0d3d736..668fe44 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -276,12 +276,13 @@ function comment_new_page_count($num_comments, $new_replies, ContentEntityInterf
     // thread with a new comment.
 
     // 1. Find all the threads with a new comment.
-    $unread_threads_query = db_select('comment')
+    $unread_threads_query = db_select('comment_field_data', 'comment')
       ->fields('comment', array('thread'))
       ->condition('entity_id', $entity->id())
       ->condition('entity_type', $entity->getEntityTypeId())
       ->condition('field_name', $field_name)
       ->condition('status', CommentInterface::PUBLISHED)
+      ->condition('default_langcode', 1)
       ->orderBy('created', 'DESC')
       ->orderBy('cid', 'DESC')
       ->range(0, $new_replies);
@@ -300,10 +301,12 @@ function comment_new_page_count($num_comments, $new_replies, ContentEntityInterf
     $first_thread = substr($first_thread, 0, -1);
 
     // Find the number of the first comment of the first unread thread.
-    $count = db_query('SELECT COUNT(*) FROM {comment} WHERE entity_id = :entity_id
+    $count = db_query('SELECT COUNT(*) FROM {comment_field_data} WHERE entity_id = :entity_id
                       AND entity_type = :entity_type
                       AND field_name = :field_name
-                      AND status = :status AND SUBSTRING(thread, 1, (LENGTH(thread) - 1)) < :thread', array(
+                      AND status = :status
+                      AND SUBSTRING(thread, 1, (LENGTH(thread) - 1)) < :thread
+                      AND default_langcode = 1', array(
       ':status' => CommentInterface::PUBLISHED,
       ':entity_id' => $entity->id(),
       ':field_name' => $field_name,
@@ -578,7 +581,7 @@ function comment_node_view_alter(array &$build, EntityInterface $node, EntityVie
  * to consider the trailing "/" so we use a substring only.
  */
 function comment_get_thread(EntityInterface $entity, $field_name, $mode, $comments_per_page, $pager_id = 0) {
-  $query = db_select('comment', 'c')
+  $query = db_select('comment_field_data', 'c')
     ->extend('Drupal\Core\Database\Query\PagerSelectExtender');
   if ($pager_id) {
     $query->element($pager_id);
@@ -588,6 +591,7 @@ function comment_get_thread(EntityInterface $entity, $field_name, $mode, $commen
     ->condition('c.entity_id', $entity->id())
     ->condition('c.entity_type', $entity->getEntityTypeId())
     ->condition('c.field_name', $field_name)
+    ->condition('default_langcode', 1)
     ->addTag('entity_access')
     ->addTag('comment_filter')
     ->addMetaData('base_table', 'comment')
@@ -595,12 +599,13 @@ function comment_get_thread(EntityInterface $entity, $field_name, $mode, $commen
     ->addMetaData('field_name', $field_name)
     ->limit($comments_per_page);
 
-  $count_query = db_select('comment', 'c');
+  $count_query = db_select('comment_field_data', 'c');
   $count_query->addExpression('COUNT(*)');
   $count_query
     ->condition('c.entity_id', $entity->id())
     ->condition('c.entity_type', $entity->getEntityTypeId())
     ->condition('c.field_name', $field_name)
+    ->condition('default_langcode', 1)
     ->addTag('entity_access')
     ->addTag('comment_filter')
     ->addMetaData('base_table', 'comment')
@@ -1019,8 +1024,8 @@ function comment_num_new($entity_id, $entity_type, $field_name = NULL, $timestam
 function comment_get_display_ordinal($cid, FieldDefinitionInterface $field_definition) {
   // Count how many comments (c1) are before $cid (c2) in display order. This is
   // the 0-based display ordinal.
-  $query = db_select('comment', 'c1');
-  $query->innerJoin('comment', 'c2', 'c2.entity_id = c1.entity_id AND c2.entity_type = c1.entity_type AND c2.field_name = c1.field_name');
+  $query = db_select('comment_field_data', 'c1');
+  $query->innerJoin('comment_field_data', 'c2', 'c2.entity_id = c1.entity_id AND c2.entity_type = c1.entity_type AND c2.field_name = c1.field_name');
   $query->addExpression('COUNT(*)', 'count');
   $query->condition('c2.cid', $cid);
   if (!user_access('administer comments')) {
@@ -1039,6 +1044,8 @@ function comment_get_display_ordinal($cid, FieldDefinitionInterface $field_defin
     // See CommentViewBuilder.
     $query->where('SUBSTRING(c1.thread, 1, (LENGTH(c1.thread) -1)) < SUBSTRING(c2.thread, 1, (LENGTH(c2.thread) -1))');
   }
+  $query->condition('c1.default_langcode', 1);
+  $query->condition('c2.default_langcode', 1);
 
   return $query->execute()->fetchField();
 }
diff --git a/core/modules/comment/comment.views.inc b/core/modules/comment/comment.views.inc
index aa6008c..52f517c 100644
--- a/core/modules/comment/comment.views.inc
+++ b/core/modules/comment/comment.views.inc
@@ -23,7 +23,15 @@ function comment_views_data() {
   $data['comment']['table']['entity type'] = 'comment';
   $data['comment']['table']['wizard_id'] = 'comment';
 
-  $data['comment']['subject'] = array(
+  $data['comment_field_data']['table']['group'] = t('Comment');
+  $data['comment_field_data']['table']['entity type'] = 'comment';
+  $data['comment_field_data']['table']['join']['comment'] = array(
+    'type' => 'INNER',
+    'left_field' => 'cid',
+    'field' => 'cid',
+  );
+
+  $data['comment_field_data']['subject'] = array(
     'title' => t('Title'),
     'help' => t('The title of the comment.'),
     'field' => array(
@@ -57,7 +65,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['name'] = array(
+  $data['comment_field_data']['name'] = array(
     'title' => t('Author'),
     'help' => t("The name of the comment's author. Can be rendered as a link to the author's homepage."),
     'field' => array(
@@ -74,7 +82,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['homepage'] = array(
+  $data['comment_field_data']['homepage'] = array(
     'title' => t("Author's website"),
     'help' => t("The website address of the comment's author. Can be rendered as a link. Will be empty if the author is a registered user."),
     'field' => array(
@@ -91,7 +99,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['hostname'] = array(
+  $data['comment_field_data']['hostname'] = array(
     'title' => t('Hostname'),
     'help' => t('Hostname of user that posted the comment.'),
     'field' => array(
@@ -108,7 +116,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['mail'] = array(
+  $data['comment_field_data']['mail'] = array(
     'title' => t('Email'),
     'help' => t('Email of user that posted the comment. Will be empty if the author is a registered user.'),
     'field' => array(
@@ -125,7 +133,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['created'] = array(
+  $data['comment_field_data']['created'] = array(
     'title' => t('Post date'),
     'help' => t('Date and time of when the comment was created.'),
     'field' => array(
@@ -158,7 +166,7 @@ function comment_views_data() {
     );
   }
 
-  $data['comment']['changed'] = array(
+  $data['comment_field_data']['changed'] = array(
     'title' => t('Updated date'),
     'help' => t('Date and time of when the comment was last updated.'),
     'field' => array(
@@ -172,7 +180,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_fulldata'] = array(
+  $data['comment_field_data']['changed_fulldata'] = array(
     'title' => t('Created date'),
     'help' => t('Date in the form of CCYYMMDD.'),
     'argument' => array(
@@ -181,7 +189,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_year_month'] = array(
+  $data['comment_field_data']['changed_year_month'] = array(
     'title' => t('Created year + month'),
     'help' => t('Date in the form of YYYYMM.'),
     'argument' => array(
@@ -190,7 +198,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_year'] = array(
+  $data['comment_field_data']['changed_year'] = array(
     'title' => t('Created year'),
     'help' => t('Date in the form of YYYY.'),
     'argument' => array(
@@ -199,7 +207,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_month'] = array(
+  $data['comment_field_data']['changed_month'] = array(
     'title' => t('Created month'),
     'help' => t('Date in the form of MM (01 - 12).'),
     'argument' => array(
@@ -208,7 +216,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_day'] = array(
+  $data['comment_field_data']['changed_day'] = array(
     'title' => t('Created day'),
     'help' => t('Date in the form of DD (01 - 31).'),
     'argument' => array(
@@ -217,7 +225,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['changed_week'] = array(
+  $data['comment_field_data']['changed_week'] = array(
     'title' => t('Created week'),
     'help' => t('Date in the form of WW (01 - 53).'),
     'argument' => array(
@@ -226,7 +234,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['status'] = array(
+  $data['comment_field_data']['status'] = array(
     'title' => t('Approved status'),
     'help' => t('Whether the comment is approved (or still in the moderation queue).'),
     'field' => array(
@@ -285,7 +293,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['thread'] = array(
+  $data['comment_field_data']['thread'] = array(
     'field' => array(
       'title' => t('Depth'),
       'help' => t('Display the depth of the comment if it is threaded.'),
@@ -298,7 +306,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['entity_id'] = array(
+  $data['comment_field_data']['entity_id'] = array(
     'title' => t('Entity ID'),
     'help' => t('The Entity ID to which the comment is a reply to.'),
     'field' => array(
@@ -315,7 +323,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['entity_type'] = array(
+  $data['comment_field_data']['entity_type'] = array(
     'title' => t('Entity type'),
     'help' => t('The Entity type to which the comment is a reply to.'),
     'field' => array(
@@ -332,7 +340,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['field_name'] = array(
+  $data['comment_field_data']['field_name'] = array(
     'title' => t('Comment field name'),
     'help' => t('The Field name from which the comment originated.'),
     'field' => array(
@@ -374,7 +382,7 @@ function comment_views_data() {
       continue;
     }
     if ($fields = \Drupal::service('comment.manager')->getFields($type)) {
-      $data['comment'][$type] = array(
+      $data['comment_field_data'][$type] = array(
         'relationship' => array(
           'title' => $entity_type->getLabel(),
           'help' => t('The @entity_type to which the comment is a reply to.', array('@entity_type' => $entity_type->getLabel())),
@@ -387,7 +395,7 @@ function comment_views_data() {
             array(
               'field' => 'entity_type',
               'value' => $type,
-              'table' => 'comment'
+              'table' => 'comment_field_data'
             ),
           ),
         ),
@@ -395,7 +403,7 @@ function comment_views_data() {
     }
   }
 
-  $data['comment']['uid'] = array(
+  $data['comment_field_data']['uid'] = array(
     'title' => t('Author uid'),
     'help' => t('If you need more fields than the uid add the comment: author relationship'),
     'relationship' => array(
@@ -417,7 +425,7 @@ function comment_views_data() {
     ),
   );
 
-  $data['comment']['pid'] = array(
+  $data['comment_field_data']['pid'] = array(
     'title' => t('Parent CID'),
     'help' => t('The Comment ID of the parent comment.'),
     'field' => array(
@@ -637,12 +645,9 @@ function comment_views_data_alter(&$data) {
         ),
       );
 
-      if ($entity_type_id == 'node') {
-        // Node properties lives in data_table.
-        $table = $entity_type->getDataTable();
-      }
-      else {
-        $table = $base_table;
+      // Multilingual properties are stored in data table.
+      if (!($table = $entity_type->getDataTable())) {
+        $table = $entity_type->getBaseTable();
       }
       $data[$table]['uid_touch'] = array(
         'title' => t('User posted or commented'),
@@ -673,7 +678,7 @@ function comment_views_data_alter(&$data) {
           'relationship' => array(
             'group' => t('Comment'),
             'label' => t('Comments'),
-            'base' => 'comment',
+            'base' => 'comment_field_data',
             'base field' => 'entity_id',
             'relationship field' => $entity_type->getKey('id'),
             'id' => 'standard',
diff --git a/core/modules/comment/config/install/views.view.comments_recent.yml b/core/modules/comment/config/install/views.view.comments_recent.yml
index 22a7ea9..1e20f75 100644
--- a/core/modules/comment/config/install/views.view.comments_recent.yml
+++ b/core/modules/comment/config/install/views.view.comments_recent.yml
@@ -54,13 +54,13 @@ display:
         node:
           field: node
           id: node
-          table: comment
+          table: comment_field_data
           required: true
           plugin_id: standard
       fields:
         subject:
           id: subject
-          table: comment
+          table: comment_field_data
           field: subject
           relationship: none
           plugin_id: comment
@@ -111,7 +111,7 @@ display:
           link_to_entity: false
         changed:
           id: changed
-          table: comment
+          table: comment_field_data
           field: changed
           relationship: none
           plugin_id: date
@@ -164,7 +164,7 @@ display:
       filters:
         status:
           value: true
-          table: comment
+          table: comment_field_data
           field: status
           id: status
           plugin_id: boolean
@@ -184,7 +184,7 @@ display:
       sorts:
         created:
           id: created
-          table: comment
+          table: comment_field_data
           field: created
           relationship: none
           group_type: group
diff --git a/core/modules/comment/src/CommentStatistics.php b/core/modules/comment/src/CommentStatistics.php
index fbbdff4..24eb09a 100644
--- a/core/modules/comment/src/CommentStatistics.php
+++ b/core/modules/comment/src/CommentStatistics.php
@@ -179,23 +179,25 @@ public function update(CommentInterface $comment) {
       return;
     }
 
-    $query = $this->database->select('comment', 'c');
+    $query = $this->database->select('comment_field_data', 'c');
     $query->addExpression('COUNT(cid)');
     $count = $query->condition('c.entity_id', $comment->getCommentedEntityId())
       ->condition('c.entity_type', $comment->getCommentedEntityTypeId())
       ->condition('c.field_name', $comment->getFieldName())
       ->condition('c.status', CommentInterface::PUBLISHED)
+      ->condition('default_langcode', 1)
       ->execute()
       ->fetchField();
 
     if ($count > 0) {
       // Comments exist.
-      $last_reply = $this->database->select('comment', 'c')
+      $last_reply = $this->database->select('comment_field_data', 'c')
         ->fields('c', array('cid', 'name', 'changed', 'uid'))
         ->condition('c.entity_id', $comment->getCommentedEntityId())
         ->condition('c.entity_type', $comment->getCommentedEntityTypeId())
         ->condition('c.field_name', $comment->getFieldName())
         ->condition('c.status', CommentInterface::PUBLISHED)
+        ->condition('default_langcode', 1)
         ->orderBy('c.created', 'DESC')
         ->range(0, 1)
         ->execute()
diff --git a/core/modules/comment/src/CommentStorage.php b/core/modules/comment/src/CommentStorage.php
index f463d0a..1591aeb 100644
--- a/core/modules/comment/src/CommentStorage.php
+++ b/core/modules/comment/src/CommentStorage.php
@@ -69,10 +69,11 @@ public function updateEntityStatistics(CommentInterface $comment) {
    * {@inheritdoc}
    */
   public function getMaxThread(EntityInterface $comment) {
-    $query = $this->database->select('comment', 'c')
+    $query = $this->database->select('comment_field_data', 'c')
       ->condition('entity_id', $comment->getCommentedEntityId())
       ->condition('field_name', $comment->getFieldName())
-      ->condition('entity_type', $comment->getCommentedEntityTypeId());
+      ->condition('entity_type', $comment->getCommentedEntityTypeId())
+      ->condition('default_langcode', 1);
     $query->addExpression('MAX(thread)', 'thread');
     return $query->execute()
       ->fetchField();
@@ -82,11 +83,12 @@ public function getMaxThread(EntityInterface $comment) {
    * {@inheritdoc}
    */
   public function getMaxThreadPerThread(EntityInterface $comment) {
-    $query = $this->database->select('comment', 'c')
+    $query = $this->database->select('comment_field_data', 'c')
       ->condition('entity_id', $comment->getCommentedEntityId())
       ->condition('field_name', $comment->getFieldName())
       ->condition('entity_type', $comment->getCommentedEntityTypeId())
-      ->condition('thread', $comment->getParentComment()->getThread() . '.%', 'LIKE');
+      ->condition('thread', $comment->getParentComment()->getThread() . '.%', 'LIKE')
+      ->condition('default_langcode', 1);
     $query->addExpression('MAX(thread)', 'thread');
     return $query->execute()
       ->fetchField();
@@ -96,9 +98,10 @@ public function getMaxThreadPerThread(EntityInterface $comment) {
    * {@inheritdoc}
    */
   public function getChildCids(array $comments) {
-    return $this->database->select('comment', 'c')
+    return $this->database->select('comment_field_data', 'c')
       ->fields('c', array('cid'))
       ->condition('pid', array_keys($comments))
+      ->condition('default_langcode', 1)
       ->execute()
       ->fetchCol();
   }
@@ -111,19 +114,16 @@ public function getSchema() {
 
     // Marking the respective fields as NOT NULL makes the indexes more
     // performant.
-    $schema['comment']['fields']['pid']['not null'] = TRUE;
-    $schema['comment']['fields']['status']['not null'] = TRUE;
-    $schema['comment']['fields']['entity_id']['not null'] = TRUE;
-    $schema['comment']['fields']['created']['not null'] = TRUE;
-    $schema['comment']['fields']['thread']['not null'] = TRUE;
-
-    unset($schema['comment']['indexes']['field__pid']);
-    unset($schema['comment']['indexes']['field__entity_id']);
-    $schema['comment']['indexes'] += array(
+    $schema['comment_field_data']['fields']['created']['not null'] = TRUE;
+    $schema['comment_field_data']['fields']['thread']['not null'] = TRUE;
+
+    unset($schema['comment_field_data']['indexes']['comment_field__pid__target_id']);
+    unset($schema['comment_field_data']['indexes']['comment_field__entity_id__target_id']);
+    $schema['comment_field_data']['indexes'] += array(
       'comment__status_pid' => array('pid', 'status'),
       'comment__num_new' => array(
         'entity_id',
-        array('entity_type', 32),
+        'entity_type',
         'comment_type',
         'status',
         'created',
@@ -132,13 +132,13 @@ public function getSchema() {
       ),
       'comment__entity_langcode' => array(
         'entity_id',
-        array('entity_type', 32),
+        'entity_type',
         'comment_type',
-        'langcode',
+        'default_langcode',
       ),
       'comment__created' => array('created'),
     );
-    $schema['comment']['foreign keys'] += array(
+    $schema['comment_field_data']['foreign keys'] += array(
       'comment__author' => array(
         'table' => 'users',
         'columns' => array('uid' => 'uid'),
@@ -152,8 +152,9 @@ public function getSchema() {
    * {@inheritdoc}
    */
   public function getUnapprovedCount() {
-    return  $this->database->select('comment', 'c')
+    return  $this->database->select('comment_field_data', 'c')
       ->condition('status', CommentInterface::NOT_PUBLISHED, '=')
+      ->condition('default_langcode', 1)
       ->countQuery()
       ->execute()
       ->fetchField();
diff --git a/core/modules/comment/src/Entity/Comment.php b/core/modules/comment/src/Entity/Comment.php
index 777d92b..46ffe6b 100644
--- a/core/modules/comment/src/Entity/Comment.php
+++ b/core/modules/comment/src/Entity/Comment.php
@@ -34,6 +34,7 @@
  *     "translation" = "Drupal\comment\CommentTranslationHandler"
  *   },
  *   base_table = "comment",
+ *   data_table = "comment_field_data",
  *   uri_callback = "comment_uri",
  *   fieldable = TRUE,
  *   translatable = TRUE,
@@ -225,28 +226,33 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['subject'] = FieldDefinition::create('string')
       ->setLabel(t('Subject'))
       ->setDescription(t('The comment title or subject.'))
+      ->setTranslatable(TRUE)
       ->setSetting('max_length', 64);
 
     $fields['uid'] = FieldDefinition::create('entity_reference')
       ->setLabel(t('User ID'))
       ->setDescription(t('The user ID of the comment author.'))
+      ->setTranslatable(TRUE)
       ->setSetting('target_type', 'user')
       ->setDefaultValue(0);
 
     $fields['name'] = FieldDefinition::create('string')
       ->setLabel(t('Name'))
       ->setDescription(t("The comment author's name."))
+      ->setTranslatable(TRUE)
       ->setSetting('max_length', 60)
       ->setDefaultValue('')
       ->addConstraint('CommentName', array());
 
     $fields['mail'] = FieldDefinition::create('email')
       ->setLabel(t('Email'))
-      ->setDescription(t("The comment author's email address."));
+      ->setDescription(t("The comment author's email address."))
+      ->setTranslatable(TRUE);
 
     $fields['homepage'] = FieldDefinition::create('uri')
       ->setLabel(t('Homepage'))
       ->setDescription(t("The comment author's home page address."))
+      ->setTranslatable(TRUE)
       // URIs are not length limited by RFC 2616, but we can only store 255
       // characters in our comment DB schema.
       ->setSetting('max_length', 255);
@@ -254,29 +260,35 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['hostname'] = FieldDefinition::create('string')
       ->setLabel(t('Hostname'))
       ->setDescription(t("The comment author's hostname."))
+      ->setTranslatable(TRUE)
       ->setSetting('max_length', 128);
 
     $fields['created'] = FieldDefinition::create('created')
       ->setLabel(t('Created'))
-      ->setDescription(t('The time that the comment was created.'));
+      ->setDescription(t('The time that the comment was created.'))
+      ->setTranslatable(TRUE);
 
     $fields['changed'] = FieldDefinition::create('changed')
       ->setLabel(t('Changed'))
-      ->setDescription(t('The time that the comment was last edited.'));
+      ->setDescription(t('The time that the comment was last edited.'))
+      ->setTranslatable(TRUE);
 
     $fields['status'] = FieldDefinition::create('boolean')
       ->setLabel(t('Publishing status'))
       ->setDescription(t('A boolean indicating whether the comment is published.'))
+      ->setTranslatable(TRUE)
       ->setDefaultValue(TRUE);
 
     $fields['thread'] = FieldDefinition::create('string')
       ->setLabel(t('Thread place'))
       ->setDescription(t("The alphadecimal representation of the comment's place in a thread, consisting of a base 36 string prefixed by an integer indicating its length."))
+      ->setTranslatable(TRUE)
       ->setSetting('max_length', 255);
 
     $fields['entity_type'] = FieldDefinition::create('string')
       ->setLabel(t('Entity type'))
-      ->setDescription(t('The entity type to which this comment is attached.'));
+      ->setDescription(t('The entity type to which this comment is attached.'))
+      ->setSetting('max_length', EntityTypeInterface::ID_MAX_LENGTH);
 
     $fields['comment_type'] = FieldDefinition::create('entity_reference')
       ->setLabel(t('Comment Type'))
@@ -286,7 +298,7 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['field_name'] = FieldDefinition::create('string')
       ->setLabel(t('Comment field name'))
       ->setDescription(t('The field name through which this comment was added.'))
-      ->setSetting('max_length', 32);
+      ->setSetting('max_length', FieldConfig::NAME_MAX_LENGTH);
 
     return $fields;
   }
diff --git a/core/modules/comment/src/Plugin/entity_reference/selection/CommentSelection.php b/core/modules/comment/src/Plugin/entity_reference/selection/CommentSelection.php
index 7a627d1..a1ebe2a 100644
--- a/core/modules/comment/src/Plugin/entity_reference/selection/CommentSelection.php
+++ b/core/modules/comment/src/Plugin/entity_reference/selection/CommentSelection.php
@@ -44,31 +44,20 @@ public function buildEntityQuery($match = NULL, $match_operator = 'CONTAINS') {
    */
   public function entityQueryAlter(SelectInterface $query) {
     $tables = $query->getTables();
-    $base_table = $tables['base_table']['alias'];
+    $data_table = 'comment_field_data';
+    if (!isset($tables['comment_field_data']['alias'])) {
+      // If no conditions join against the comment data table, it should be
+      // joined manually to allow node access processing.
+      $query->innerJoin($data_table, NULL, "base_table.cid = $data_table.cid AND $data_table.default_langcode = 1");
+    }
 
     // The Comment module doesn't implement any proper comment access,
     // and as a consequence doesn't make sure that comments cannot be viewed
     // when the user doesn't have access to the node.
-    $node_alias = $query->innerJoin('node_field_data', 'n', '%alias.nid = ' . $base_table . '.entity_id AND ' . $base_table . ".entity_type = 'node'");
+    $node_alias = $query->innerJoin('node_field_data', 'n', '%alias.nid = ' . $data_table . '.entity_id AND ' . $data_table . ".entity_type = 'node'");
     // Pass the query to the node access control.
     $this->reAlterQuery($query, 'node_access', $node_alias);
 
-    // Alas, the comment entity exposes a bundle, but doesn't have a bundle
-    // column in the database. We have to alter the query ourselves to go fetch
-    // the bundle.
-    $conditions = &$query->conditions();
-    foreach ($conditions as $key => &$condition) {
-      if ($key !== '#conjunction' && is_string($condition['field']) && $condition['field'] === 'node_type') {
-        $condition['field'] = $node_alias . '.type';
-        foreach ($condition['value'] as &$value) {
-          if (substr($value, 0, 13) == 'comment_node_') {
-            $value = substr($value, 13);
-          }
-        }
-        break;
-      }
-    }
-
     // Passing the query to node_query_node_access_alter() is sadly
     // insufficient for nodes.
     // @see SelectionEntityTypeNode::entityQueryAlter()
diff --git a/core/modules/comment/src/Plugin/views/field/Comment.php b/core/modules/comment/src/Plugin/views/field/Comment.php
index df621c8..1a47a4a 100644
--- a/core/modules/comment/src/Plugin/views/field/Comment.php
+++ b/core/modules/comment/src/Plugin/views/field/Comment.php
@@ -38,8 +38,14 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
 
     if (!empty($this->options['link_to_comment'])) {
       $this->additional_fields['cid'] = 'cid';
-      $this->additional_fields['entity_id'] = 'entity_id';
-      $this->additional_fields['entity_type'] = 'entity_type';
+      $this->additional_fields['entity_id'] = array(
+        'table' => 'comment_field_data',
+        'field' => 'entity_id'
+      );
+      $this->additional_fields['entity_type'] = array(
+        'table' => 'comment_field_data',
+        'field' => 'entity_type'
+      );
     }
   }
 
@@ -88,7 +94,7 @@ protected function renderLink($data, ResultRow $values) {
         $this->options['alter']['path'] = "comment/" . $cid;
         $this->options['alter']['fragment'] = "comment-" . $cid;
       }
-      // If there is no comment link to the node.
+      // If there is no comment link to the entity.
       elseif ($this->options['link_to_entity']) {
         $entity_id = $this->getValue($values, 'entity_id');
         $entity_type = $this->getValue($values, 'entity_type');
diff --git a/core/modules/comment/src/Plugin/views/field/LinkApprove.php b/core/modules/comment/src/Plugin/views/field/LinkApprove.php
index 9fb8e00..36563f9 100644
--- a/core/modules/comment/src/Plugin/views/field/LinkApprove.php
+++ b/core/modules/comment/src/Plugin/views/field/LinkApprove.php
@@ -42,7 +42,7 @@ public function access(AccountInterface $account) {
   protected function renderLink($data, ResultRow $values) {
     $status = $this->getValue($values, 'status');
 
-    // Don't show an approve link on published nodes.
+    // Don't show an approve link on published comment.
     if ($status == CommentInterface::PUBLISHED) {
       return;
     }
diff --git a/core/modules/comment/src/Plugin/views/field/NodeNewComments.php b/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
index 5ccf4e2..3d7e9ce 100644
--- a/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
+++ b/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
@@ -118,7 +118,7 @@ public function preRender(&$values) {
     }
 
     if ($nids) {
-      $result = $this->database->query("SELECT n.nid, COUNT(c.cid) as num_comments FROM {node} n INNER JOIN {comment} c ON n.nid = c.entity_id AND c.entity_type = 'node'
+      $result = $this->database->query("SELECT n.nid, COUNT(c.cid) as num_comments FROM {node} n INNER JOIN {comment_field_data} c ON n.nid = c.entity_id AND c.entity_type = 'node' AND c.default_langcode = 1
         LEFT JOIN {history} h ON h.nid = n.nid AND h.uid = :h_uid WHERE n.nid IN (:nids)
         AND c.changed > GREATEST(COALESCE(h.timestamp, :timestamp), :timestamp) AND c.status = :status GROUP BY n.nid", array(
         ':status' => CommentInterface::PUBLISHED,
diff --git a/core/modules/comment/src/Plugin/views/wizard/Comment.php b/core/modules/comment/src/Plugin/views/wizard/Comment.php
index 09fb54e..c2c4ff4 100644
--- a/core/modules/comment/src/Plugin/views/wizard/Comment.php
+++ b/core/modules/comment/src/Plugin/views/wizard/Comment.php
@@ -50,7 +50,7 @@ class Comment extends WizardPluginBase {
   protected $filters = array(
     'status' => array(
       'value' => TRUE,
-      'table' => 'comment',
+      'table' => 'comment_field_data',
       'field' => 'status',
       'provider' => 'comment'
     ),
@@ -144,7 +144,7 @@ protected function defaultDisplayOptions() {
 
     // Add a relationship to nodes.
     $display_options['relationships']['node']['id'] = 'node';
-    $display_options['relationships']['node']['table'] = 'comment';
+    $display_options['relationships']['node']['table'] = 'comment_field_data';
     $display_options['relationships']['node']['field'] = 'node';
     $display_options['relationships']['node']['required'] = 1;
     $display_options['relationships']['node']['plugin_id'] = 'standard';
@@ -155,7 +155,7 @@ protected function defaultDisplayOptions() {
 
     /* Field: Comment: Title */
     $display_options['fields']['subject']['id'] = 'subject';
-    $display_options['fields']['subject']['table'] = 'comment';
+    $display_options['fields']['subject']['table'] = 'comment_field_data';
     $display_options['fields']['subject']['field'] = 'subject';
     $display_options['fields']['subject']['provider'] = 'comment';
     $display_options['fields']['subject']['label'] = '';
diff --git a/core/modules/comment/src/Tests/CommentLanguageTest.php b/core/modules/comment/src/Tests/CommentLanguageTest.php
index d139a38..2982134 100644
--- a/core/modules/comment/src/Tests/CommentLanguageTest.php
+++ b/core/modules/comment/src/Tests/CommentLanguageTest.php
@@ -118,11 +118,12 @@ function testCommentLanguage() {
         $this->drupalPostForm(NULL, $edit, t('Save'));
 
         // Check that comment language matches the current content language.
-        $cid = db_select('comment', 'c')
+        $cid = db_select('comment_field_data', 'c')
           ->fields('c', array('cid'))
           ->condition('entity_id', $node->id())
           ->condition('entity_type', 'node')
           ->condition('field_name', 'comment')
+          ->condition('default_langcode', 1)
           ->orderBy('cid', 'DESC')
           ->range(0, 1)
           ->execute()
diff --git a/core/modules/comment/src/Tests/Views/DefaultViewRecentCommentsTest.php b/core/modules/comment/src/Tests/Views/DefaultViewRecentCommentsTest.php
index b6fdce3..4cca47c 100644
--- a/core/modules/comment/src/Tests/Views/DefaultViewRecentCommentsTest.php
+++ b/core/modules/comment/src/Tests/Views/DefaultViewRecentCommentsTest.php
@@ -121,10 +121,10 @@ public function testBlockDisplay() {
     $this->executeView($view);
 
     $map = array(
-      'comment_entity_id' => 'entity_id',
-      'comment_subject' => 'subject',
+      'comment_field_data_entity_id' => 'entity_id',
+      'comment_field_data_subject' => 'subject',
       'cid' => 'cid',
-      'comment_created' => 'created'
+      'comment_field_data_created' => 'created'
     );
     $expected_result = array();
     foreach (array_values($this->commentsCreated) as $key => $comment) {
diff --git a/core/modules/comment/src/Tests/Views/WizardTest.php b/core/modules/comment/src/Tests/Views/WizardTest.php
index 6ced3f6..88ebe4b 100644
--- a/core/modules/comment/src/Tests/Views/WizardTest.php
+++ b/core/modules/comment/src/Tests/Views/WizardTest.php
@@ -88,7 +88,7 @@ public function testCommentWizard() {
     $this->assertEqual($row['type'], 'entity:comment');
 
     // Check for the default filters.
-    $this->assertEqual($view->filter['status']->table, 'comment');
+    $this->assertEqual($view->filter['status']->table, 'comment_field_data');
     $this->assertEqual($view->filter['status']->field, 'status');
     $this->assertTrue($view->filter['status']->value);
     $this->assertEqual($view->filter['status_node']->table, 'node_field_data');
@@ -96,7 +96,7 @@ public function testCommentWizard() {
     $this->assertTrue($view->filter['status_node']->value);
 
     // Check for the default fields.
-    $this->assertEqual($view->field['subject']->table, 'comment');
+    $this->assertEqual($view->field['subject']->table, 'comment_field_data');
     $this->assertEqual($view->field['subject']->field, 'subject');
   }
 
diff --git a/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_row.yml b/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_row.yml
index 2a443b5..37f34fa 100644
--- a/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_row.yml
+++ b/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_row.yml
@@ -75,14 +75,14 @@ display:
           field: node
           id: node
           required: true
-          table: comment
+          table: comment_field_data
           relationship: none
           group_type: group
           admin_label: Content
       fields:
         subject:
           id: subject
-          table: comment
+          table: comment_field_data
           field: subject
           label: ''
           alter:
@@ -115,7 +115,7 @@ display:
       filters:
         status:
           value: '1'
-          table: comment
+          table: comment_field_data
           field: status
           id: status
           expose:
diff --git a/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_rss.yml b/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_rss.yml
index 44245b7..be5db60 100644
--- a/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_rss.yml
+++ b/core/modules/comment/tests/modules/comment_test_views/test_views/views.view.test_comment_rss.yml
@@ -36,12 +36,12 @@ display:
           field: node
           id: node
           required: true
-          table: comment
+          table: comment_field_data
           provider: views
       fields:
         subject:
           id: subject
-          table: comment
+          table: comment_field_data
           field: subject
           plugin_id: comment
           label: ''
diff --git a/core/modules/content_translation/src/Tests/ContentTranslationSettingsTest.php b/core/modules/content_translation/src/Tests/ContentTranslationSettingsTest.php
index 0db6520..e724bad 100644
--- a/core/modules/content_translation/src/Tests/ContentTranslationSettingsTest.php
+++ b/core/modules/content_translation/src/Tests/ContentTranslationSettingsTest.php
@@ -69,6 +69,8 @@ function testSettingsUI() {
     $edit = array(
       'entity_types[comment]' => TRUE,
       'settings[comment][comment_article][translatable]' => TRUE,
+      // Subject field translatable by default.
+      'settings[comment][comment_article][fields][subject]' => FALSE,
     );
     $this->assertSettings('comment', 'comment_article', FALSE, $edit);
     $xpath_err = '//div[contains(@class, "error")]';
@@ -94,13 +96,24 @@ function testSettingsUI() {
       'settings[comment][comment_article][settings][language][language_show]' => TRUE,
       'settings[comment][comment_article][translatable]' => TRUE,
       'settings[comment][comment_article][fields][comment_body]' => TRUE,
+      // Override both comment subject fields to untranslatable.
+      'settings[comment][comment_article][fields][subject]' => FALSE,
+      'settings[comment][comment][fields][subject]' => FALSE,
     );
     $this->assertSettings('comment', 'comment_article', TRUE, $edit);
     $definition = $this->entityManager()->getFieldDefinitions('comment', 'comment_article')['comment_body'];
     $this->assertTrue($definition->isTranslatable(), 'Article comment body is translatable.');
+    $definition = $this->entityManager()->getFieldDefinitions('comment', 'comment_article')['subject'];
+    $this->assertFalse($definition->isTranslatable(), 'Article comment subject is not translatable.');
+
     $definition = $this->entityManager()->getFieldDefinitions('comment', 'comment')['comment_body'];
     $this->assertFalse($definition->isTranslatable(), 'Page comment body is not translatable.');
-    $this->assertNull(content_translation_get_config('comment', 'comment_article', 'fields'), 'Configurable fields are not saved to content_translation.settings.');
+    $definition = $this->entityManager()->getFieldDefinitions('comment', 'comment')['subject'];
+    $this->assertFalse($definition->isTranslatable(), 'Page comment subject is not translatable.');
+
+    $settings = content_translation_get_config('comment', 'comment_article', 'fields');
+    $this->assertFalse(isset($settings['comment_body']), 'Configurable fields are not saved to content_translation.settings.');
+    $this->assertTrue(isset($settings['subject']), 'Base fields are saved to content_translation.settings.');
 
     // Test that translation can be enabled for base fields.
     $edit = array(
diff --git a/core/modules/forum/src/ForumIndexStorage.php b/core/modules/forum/src/ForumIndexStorage.php
index d732806..c7fa74f 100644
--- a/core/modules/forum/src/ForumIndexStorage.php
+++ b/core/modules/forum/src/ForumIndexStorage.php
@@ -96,14 +96,14 @@ public function update(NodeInterface $node) {
    */
   public function updateIndex(NodeInterface $node) {
     $nid = $node->id();
-    $count = $this->database->query("SELECT COUNT(cid) FROM {comment} c INNER JOIN {forum_index} i ON c.entity_id = i.nid WHERE c.entity_id = :nid AND c.field_name = 'comment_forum' AND c.entity_type = 'node' AND c.status = :status", array(
+    $count = $this->database->query("SELECT COUNT(cid) FROM {comment_field_data} c INNER JOIN {forum_index} i ON c.entity_id = i.nid WHERE c.entity_id = :nid AND c.field_name = 'comment_forum' AND c.entity_type = 'node' AND c.status = :status AND c.default_langcode = 1", array(
       ':nid' => $nid,
       ':status' => CommentInterface::PUBLISHED,
     ))->fetchField();
 
     if ($count > 0) {
       // Comments exist.
-      $last_reply = $this->database->queryRange("SELECT cid, name, created, uid FROM {comment} WHERE entity_id = :nid AND field_name = 'comment_forum' AND entity_type = 'node' AND status = :status ORDER BY cid DESC", 0, 1, array(
+      $last_reply = $this->database->queryRange("SELECT cid, name, created, uid FROM {comment_field_data} WHERE entity_id = :nid AND field_name = 'comment_forum' AND entity_type = 'node' AND status = :status AND default_langcode = 1 ORDER BY cid DESC", 0, 1, array(
         ':nid' => $nid,
         ':status' => CommentInterface::PUBLISHED,
       ))->fetchObject();
diff --git a/core/modules/tracker/tracker.module b/core/modules/tracker/tracker.module
index 68b9eb8..d1c911b 100644
--- a/core/modules/tracker/tracker.module
+++ b/core/modules/tracker/tracker.module
@@ -81,7 +81,7 @@ function tracker_cron() {
         ))
         ->execute();
 
-      $query = db_select('comment', 'c', array('target' => 'replica'));
+      $query = db_select('comment_field_data', 'c', array('target' => 'replica'));
       // Force PostgreSQL to do an implicit cast by adding 0.
       $query->addExpression('0 + :changed', 'changed', array(':changed' => $changed));
       $query->addField('c', 'status', 'published');
@@ -92,7 +92,8 @@ function tracker_cron() {
         ->condition('c.entity_id', $row->nid)
         ->condition('c.entity_type', 'node')
         ->condition('c.uid', $row->uid, '<>')
-        ->condition('c.status', CommentInterface::PUBLISHED);
+        ->condition('c.status', CommentInterface::PUBLISHED)
+        ->condition('c.default_langcode', 1);
 
       // Insert the user-level data for the commenters (except if a commenter
       // is the node's author).
@@ -279,7 +280,7 @@ function _tracker_calculate_changed($nid) {
   // @todo This should be actually filtering on the desired language and just
   //   fall back to the default language.
   $changed = db_query('SELECT changed FROM {node_field_data} WHERE nid = :nid AND default_langcode = 1 ORDER BY changed DESC', array(':nid' => $nid), array('target' => 'replica'))->fetchField();
-  $latest_comment = db_query_range("SELECT cid, changed FROM {comment} WHERE entity_type = 'node' AND entity_id = :nid AND status = :status ORDER BY changed DESC", 0, 1, array(
+  $latest_comment = db_query_range("SELECT cid, changed FROM {comment_field_data} WHERE entity_type = 'node' AND entity_id = :nid AND status = :status AND default_langcode = 1 ORDER BY changed DESC", 0, 1, array(
     ':nid' => $nid,
     ':status' => CommentInterface::PUBLISHED,
   ), array('target' => 'replica'))->fetchObject();
@@ -312,7 +313,7 @@ function _tracker_remove($nid, $uid = NULL, $changed = NULL) {
     // Or if they have commented on the node.
     if (!$keep_subscription) {
       // Check if the user has commented at least once on the given nid.
-      $keep_subscription = db_query_range("SELECT COUNT(*) FROM {comment} WHERE entity_type = 'node' AND entity_id = :nid AND uid = :uid AND status = :status", 0, 1, array(
+      $keep_subscription = db_query_range("SELECT COUNT(*) FROM {comment_field_data} WHERE entity_type = 'node' AND entity_id = :nid AND uid = :uid AND status = :status AND default_langcode = 1", 0, 1, array(
         ':nid' => $nid,
         ':uid' => $uid,
         ':status' => CommentInterface::PUBLISHED,
diff --git a/core/modules/views/src/Tests/Handler/HandlerTest.php b/core/modules/views/src/Tests/Handler/HandlerTest.php
index 14a5286..0e67316 100644
--- a/core/modules/views/src/Tests/Handler/HandlerTest.php
+++ b/core/modules/views/src/Tests/Handler/HandlerTest.php
@@ -284,7 +284,7 @@ public function testSetRelationship() {
     // Setup a broken relationship.
     $view->addHandler('default', 'relationship', $this->randomName(), $this->randomName(), array(), 'broken_relationship');
     // Setup a valid relationship.
-    $view->addHandler('default', 'relationship', 'comment', 'node', array('relationship' => 'cid'), 'valid_relationship');
+    $view->addHandler('default', 'relationship', 'comment_field_data', 'node', array('relationship' => 'cid'), 'valid_relationship');
     $view->initHandlers();
     $field = $view->field['title'];
 
diff --git a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_destroy.yml b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_destroy.yml
index dfe9d4c..5dfd8c9 100644
--- a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_destroy.yml
+++ b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_destroy.yml
@@ -155,14 +155,14 @@ display:
         pid:
           field: pid
           id: pid
-          table: comment
+          table: comment_field_data
           relationship: comment_cid
           plugin_id: standard
           provider: views
         uid:
           field: uid
           id: uid
-          table: comment
+          table: comment_field_data
           relationship: comment_cid
           plugin_id: standard
           provider: views
diff --git a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_field_get_entity.yml b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_field_get_entity.yml
index 3b634c6..ab11335 100644
--- a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_field_get_entity.yml
+++ b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_field_get_entity.yml
@@ -45,7 +45,7 @@ display:
           field: node
           id: node
           required: '1'
-          table: comment
+          table: comment_field_data
           plugin_id: standard
           provider: views
         uid:
diff --git a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_handler_relationships.yml b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_handler_relationships.yml
index 9f62495..8a377d9 100644
--- a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_handler_relationships.yml
+++ b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_handler_relationships.yml
@@ -21,7 +21,7 @@ display:
           provider: views
         nid:
           id: nid
-          table: comment
+          table: comment_field_data
           field: node
           relationship: comment_cid
           plugin_id: standard