diff --git a/core/modules/comment/migration_templates/d6_comment_entity_display.yml b/core/modules/comment/migration_templates/d6_comment_entity_display.yml
index c650673188..89e159c47c 100644
--- a/core/modules/comment/migration_templates/d6_comment_entity_display.yml
+++ b/core/modules/comment/migration_templates/d6_comment_entity_display.yml
@@ -3,10 +3,9 @@ label: Comment display configuration
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable
+  plugin: d6_node_type
   constants:
     entity_type: node
-    field_name: comment
     view_mode: default
     options:
       label: hidden
@@ -14,10 +13,17 @@ source:
       weight: 20
 process:
   entity_type: 'constants/entity_type'
-  field_name: 'constants/field_name'
+  field_name:
+    -
+      plugin: migration_lookup
+      source: type
+      migration: d6_comment_type
+    -
+      plugin: skip_on_empty
+      method: row
   view_mode: 'constants/view_mode'
   options: 'constants/options'
-  bundle: node_type
+  bundle: type
 destination:
   plugin: component_entity_display
 migration_dependencies:
diff --git a/core/modules/comment/migration_templates/d6_comment_entity_form_display.yml b/core/modules/comment/migration_templates/d6_comment_entity_form_display.yml
index c33685feb6..274f3de96d 100644
--- a/core/modules/comment/migration_templates/d6_comment_entity_form_display.yml
+++ b/core/modules/comment/migration_templates/d6_comment_entity_form_display.yml
@@ -3,20 +3,26 @@ label: Comment field form display configuration
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable
+  plugin: d6_node_type
   constants:
     entity_type: node
-    field_name: comment
     form_mode: default
     options:
       type: comment_default
       weight: 20
 process:
   entity_type: 'constants/entity_type'
-  field_name: 'constants/field_name'
+  field_name:
+    -
+      plugin: migration_lookup
+      source: type
+      migration: d6_comment_type
+    -
+      plugin: skip_on_empty
+      method: row
   form_mode: 'constants/form_mode'
   options: 'constants/options'
-  bundle: node_type
+  bundle: type
 destination:
   plugin: component_entity_form_display
 migration_dependencies:
diff --git a/core/modules/comment/migration_templates/d6_comment_entity_form_display_subject.yml b/core/modules/comment/migration_templates/d6_comment_entity_form_display_subject.yml
index abe6191b8c..8c293ff831 100644
--- a/core/modules/comment/migration_templates/d6_comment_entity_form_display_subject.yml
+++ b/core/modules/comment/migration_templates/d6_comment_entity_form_display_subject.yml
@@ -3,7 +3,7 @@ label: Comment subject form display configuration
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable_per_comment_type
+  plugin: d6_node_type
   constants:
     entity_type: comment
     field_name: subject
@@ -16,14 +16,23 @@ process:
   field_name: 'constants/field_name'
   form_mode: 'constants/form_mode'
   options: 'constants/options'
+  bundle:
+    -
+      plugin: migration_lookup
+      source: type
+      migration: d6_comment_type
+    -
+      plugin: skip_on_empty
+      method: row
   hidden:
     plugin: static_map
-    source: comment_type
-    default_value: false
+    source: comment_subject_field
+    bypass: true
     map:
-      comment_no_subject: true # Hide subject field
-      comment: false
-  bundle: comment_type
+      # If comment_subject_field = FALSE, then hidden = TRUE.
+      0: true
+      # If comment_subject_field = TRUE, then hidden = FALSE.
+      1: false
 destination:
   plugin: component_entity_form_display
 migration_dependencies:
diff --git a/core/modules/comment/migration_templates/d6_comment_field.yml b/core/modules/comment/migration_templates/d6_comment_field.yml
index d14d1aa4fc..b9a5dea132 100644
--- a/core/modules/comment/migration_templates/d6_comment_field.yml
+++ b/core/modules/comment/migration_templates/d6_comment_field.yml
@@ -3,15 +3,22 @@ label: Comment field configuration
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable_per_comment_type
+  plugin: d6_node_type
   constants:
     entity_type: node
     type: comment
 process:
   entity_type: 'constants/entity_type'
-  field_name: comment_type
+  field_name:
+    -
+      plugin: migration_lookup
+      source: type
+      migration: d6_comment_type
+    -
+      plugin: skip_on_empty
+      method: row
   type: 'constants/type'
-  'settings/comment_type': comment_type
+  'settings/comment_type': '@field_name'
 destination:
   plugin: entity:field_storage_config
   dependencies:
diff --git a/core/modules/comment/migration_templates/d6_comment_field_instance.yml b/core/modules/comment/migration_templates/d6_comment_field_instance.yml
index d708619e1e..d3e7207b5b 100644
--- a/core/modules/comment/migration_templates/d6_comment_field_instance.yml
+++ b/core/modules/comment/migration_templates/d6_comment_field_instance.yml
@@ -3,7 +3,7 @@ label: Comment field instance configuration
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable
+  plugin: d6_node_type
   constants:
     entity_type: node
     label: Comments
@@ -13,12 +13,14 @@ process:
   label: 'constants/label'
   required: 'constants/required'
   field_name:
-    plugin: static_map
-    source: comment_subject_field
-    default_value: comment
-    map:
-      0: comment_no_subject
-  bundle: node_type
+    -
+      plugin: migration_lookup
+      source: type
+      migration: d6_comment_type
+    -
+      plugin: skip_on_empty
+      method: row
+  bundle: type
   'default_value/0/status': comment
   'settings/default_mode':
     plugin: static_map
diff --git a/core/modules/comment/migration_templates/d6_comment_type.yml b/core/modules/comment/migration_templates/d6_comment_type.yml
index 69a2bd8651..d3d85e4ab7 100644
--- a/core/modules/comment/migration_templates/d6_comment_type.yml
+++ b/core/modules/comment/migration_templates/d6_comment_type.yml
@@ -3,13 +3,17 @@ label: Comment type
 migration_tags:
   - Drupal 6
 source:
-  plugin: d6_comment_variable_per_comment_type
+  plugin: d6_node_type
   constants:
     entity_type: node
+    id_prefix: 'comment_node_'
 process:
   target_entity_type_id: 'constants/entity_type'
-  id: comment_type
-  label: label
-  description: description
+  id:
+    plugin: concat
+    source:
+      - 'constants/id_prefix'
+      - type
+  label: name
 destination:
   plugin: entity:comment_type
diff --git a/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariable.php b/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariable.php
deleted file mode 100644
index a56fb4dc21..0000000000
--- a/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariable.php
+++ /dev/null
@@ -1,108 +0,0 @@
-<?php
-
-namespace Drupal\comment\Plugin\migrate\source\d6;
-
-use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;
-use Drupal\migrate\Plugin\migrate\source\DummyQueryTrait;
-
-/**
- * @MigrateSource(
- *   id = "d6_comment_variable"
- * )
- */
-class CommentVariable extends DrupalSqlBase {
-
-  use DummyQueryTrait;
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function initializeIterator() {
-    return new \ArrayIterator($this->getCommentVariables());
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function count() {
-    return count($this->getCommentVariables());
-  }
-
-  /**
-   * Retrieves the values of the comment variables grouped by node type.
-   *
-   * @return array
-   */
-  protected function getCommentVariables() {
-    $comment_prefixes = array_keys($this->commentPrefixes());
-    $variables = [];
-    $node_types = $this->select('node_type', 'nt')
-      ->fields('nt', ['type'])
-      ->execute()
-      ->fetchCol();
-    foreach ($node_types as $node_type) {
-      foreach ($comment_prefixes as $prefix) {
-        $variables[] = $prefix . '_' . $node_type;
-      }
-    }
-    $return = [];
-    $values = $this->select('variable', 'v')
-      ->fields('v', ['name', 'value'])
-      ->condition('name', $variables, 'IN')
-      ->execute()
-      ->fetchAllKeyed();
-    foreach ($node_types as $node_type) {
-      foreach ($comment_prefixes as $prefix) {
-        $name = $prefix . '_' . $node_type;
-        if (isset($values[$name])) {
-          $return[$node_type][$prefix] = unserialize($values[$name]);
-        }
-      }
-    }
-    // The return key will not be used so move it inside the row. This could
-    // not be done sooner because otherwise empty rows would be created with
-    // just the node type in it.
-    foreach ($return as $node_type => $data) {
-      $return[$node_type]['node_type'] = $node_type;
-      $return[$node_type]['comment_type'] = empty($data['comment_subject_field']) ?
-        'comment_no_subject' : 'comment';
-    }
-    return $return;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function fields() {
-    return $this->commentPrefixes() + [
-      'node_type' => $this->t('The node type'),
-      'comment_type' => $this->t('The comment type'),
-    ];
-  }
-
-  /**
-   * Comment related data for fields.
-   */
-  protected function commentPrefixes() {
-    return [
-      'comment' => $this->t('Default comment setting'),
-      'comment_default_mode' => $this->t('Default display mode'),
-      'comment_default_order' => $this->t('Default display order'),
-      'comment_default_per_page' => $this->t('Default comments per page'),
-      'comment_controls' => $this->t('Comment controls'),
-      'comment_anonymous' => $this->t('Anonymous commenting'),
-      'comment_subject_field' => $this->t('Comment subject field'),
-      'comment_preview' => $this->t('Preview comment'),
-      'comment_form_location' => $this->t('Location of comment submission form'),
-    ];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getIds() {
-    $ids['node_type']['type'] = 'string';
-    return $ids;
-  }
-
-}
diff --git a/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariablePerCommentType.php b/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariablePerCommentType.php
deleted file mode 100644
index 0eea68608c..0000000000
--- a/core/modules/comment/src/Plugin/migrate/source/d6/CommentVariablePerCommentType.php
+++ /dev/null
@@ -1,62 +0,0 @@
-<?php
-
-namespace Drupal\comment\Plugin\migrate\source\d6;
-
-/**
- * @MigrateSource(
- *   id = "d6_comment_variable_per_comment_type"
- * )
- */
-class CommentVariablePerCommentType extends CommentVariable {
-
-  /**
-   * Retrieves the values of the comment variables grouped by comment type.
-   *
-   * @return array
-   */
-  protected function getCommentVariables() {
-    $node_types = parent::getCommentVariables();
-    // The return key used to separate comment types with hidden subject field.
-    $return = [];
-    foreach ($node_types as $node_type => $data) {
-      // Only 2 comment types depending on subject field visibility.
-      if (!empty($data['comment_subject_field'])) {
-        // Default label and description should be set in migration.
-        $return['comment'] = [
-          'comment_type' => 'comment',
-          'label' => $this->t('Default comments'),
-          'description' => $this->t('Allows commenting on content')
-        ];
-      }
-      else {
-        // Provide a special comment type with hidden subject field.
-        $return['comment_no_subject'] = [
-          'comment_type' => 'comment_no_subject',
-          'label' => $this->t('Comments without subject field'),
-          'description' => $this->t('Allows commenting on content, comments without subject field')
-        ];
-      }
-    }
-    return $return;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function fields() {
-    return [
-      'comment_type' => $this->t('The comment type'),
-      'label' => $this->t('The comment type label'),
-      'description' => $this->t('The comment type description'),
-    ];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getIds() {
-    $ids['comment_type']['type'] = 'string';
-    return $ids;
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityDisplayTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityDisplayTest.php
new file mode 100644
index 0000000000..b00c7e79f0
--- /dev/null
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityDisplayTest.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace Drupal\Tests\comment\Kernel\Migrate\d6;
+
+/**
+ * Upgrade comment variables to entity.display.node.*.default.yml.
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateCommentEntityDisplayTest extends MigrateCommentVariableDisplayBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['menu_ui'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->executeMigration('d6_comment_entity_display');
+  }
+
+  /**
+   * Asserts various aspects of the display of a node type comment field.
+   *
+   * @param string $node_type
+   *   The node type ID.
+   */
+  protected function assertComponent($node_type) {
+    $component = entity_get_display('node', $node_type, 'default')
+      ->getComponent('comment_node_' . $node_type);
+
+    $this->assertInternalType('array', $component);
+    $this->assertSame('hidden', $component['label']);
+    $this->assertSame('comment_default', $component['type']);
+    $this->assertSame(20, $component['weight']);
+  }
+
+  /**
+   * Tests comment variables migrated into an entity display.
+   */
+  public function testCommentEntityDisplay() {
+    $this->assertComponent('page');
+    $this->assertComponent('story');
+    $this->assertComponent('article');
+  }
+
+}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplaySubjectTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplaySubjectTest.php
new file mode 100644
index 0000000000..6bc312204e
--- /dev/null
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplaySubjectTest.php
@@ -0,0 +1,75 @@
+<?php
+
+namespace Drupal\Tests\comment\Kernel\Migrate\d6;
+
+use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
+
+/**
+ * Upgrade comment subject variable to core.entity_form_display.comment.*.default.yml
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateCommentEntityFormDisplaySubjectTest extends MigrateDrupal6TestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['comment'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installConfig(['comment']);
+    $this->executeMigrations([
+      'd6_comment_type',
+      'd6_comment_entity_form_display_subject',
+    ]);
+  }
+
+  /**
+   * Asserts that the comment subject field is visible for a node type.
+   *
+   * @param string $node_type
+   *   The node type ID.
+   */
+  protected function assertSubjectVisible($node_type) {
+    $component = entity_get_form_display('comment', "comment_node_$node_type", 'default')
+      ->getComponent('subject');
+
+    $this->assertInternalType('array', $component);
+    $this->assertSame('string_textfield', $component['type']);
+    $this->assertSame(10, $component['weight']);
+  }
+
+  /**
+   * Asserts that the comment subject field is not visible for a node type.
+   *
+   * @param string $node_type
+   *   The node type ID.
+   */
+  protected function assertSubjectNotVisible($node_type) {
+    $component = entity_get_form_display('comment', "comment_node_$node_type", 'default')
+      ->getComponent('subject');
+
+    $this->assertNull($component);
+  }
+
+  /**
+   * Tests comment subject variable migrated into an entity display.
+   */
+  public function testCommentEntityFormDisplay() {
+    $this->assertSubjectVisible('article');
+    $this->assertSubjectVisible('company');
+    $this->assertSubjectVisible('employee');
+    $this->assertSubjectVisible('page');
+    $this->assertSubjectVisible('sponsor');
+    $this->assertSubjectNotVisible('story');
+    $this->assertSubjectVisible('test_event');
+    $this->assertSubjectVisible('test_page');
+    $this->assertSubjectVisible('test_planet');
+    $this->assertSubjectVisible('test_story');
+  }
+
+}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplayTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplayTest.php
new file mode 100644
index 0000000000..46eadb5865
--- /dev/null
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentEntityFormDisplayTest.php
@@ -0,0 +1,49 @@
+<?php
+
+namespace Drupal\Tests\comment\Kernel\Migrate\d6;
+
+/**
+ * Upgrade comment variables to core.entity_form_display.node.*.default.yml.
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateCommentEntityFormDisplayTest extends MigrateCommentVariableDisplayBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['menu_ui'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->executeMigration('d6_comment_entity_form_display');
+  }
+
+  /**
+   * Asserts various aspects of the form display of a node type comment field.
+   *
+   * @param string $node_type
+   *   The node type ID.
+   */
+  protected function assertComponent($node_type) {
+    $component = entity_get_form_display('node', $node_type, 'default')
+      ->getComponent('comment_node_' . $node_type);
+
+    $this->assertInternalType('array', $component);
+    $this->assertSame('comment_default', $component['type']);
+    $this->assertSame(20, $component['weight']);
+  }
+
+  /**
+   * Tests comment variables migrated into an entity display.
+   */
+  public function testCommentEntityFormDisplay() {
+    $this->assertComponent('page');
+    $this->assertComponent('article');
+    $this->assertComponent('story');
+  }
+
+}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldInstanceTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldInstanceTest.php
new file mode 100644
index 0000000000..7651717092
--- /dev/null
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldInstanceTest.php
@@ -0,0 +1,71 @@
+<?php
+
+namespace Drupal\Tests\comment\Kernel\Migrate\d6;
+
+use Drupal\comment\CommentManagerInterface;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
+
+/**
+ * Upgrade comment variables to field.instance.node.*.comment.yml.
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateCommentFieldInstanceTest extends MigrateDrupal6TestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['comment', 'menu_ui'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installConfig(['comment']);
+    $this->migrateContentTypes();
+    $this->executeMigrations([
+      'd6_comment_type',
+      'd6_comment_field',
+      'd6_comment_field_instance',
+    ]);
+  }
+
+  /**
+   * Asserts various aspects of a comment field for a node type.
+   *
+   * @param string $node_type
+   *   The node type ID.
+   * @param mixed $default_mode
+   *   The expected default comment mode.
+   * @param int $per_page
+   *   The expected number of comments per page.
+   * @param int $anonymous
+   *   Whether anonymous commenting is expected to be enabled.
+   * @param bool $form_location
+   *   The location of the comment form.
+   * @param int $preview
+   *   Whether previewing comments is expected to be enabled.
+   */
+  protected function assertCommentField($node_type, $default_mode, $per_page, $anonymous, $form_location, $preview) {
+    $id = "node.$node_type.comment_node_$node_type";
+    $field = FieldConfig::load($id);
+
+    $this->assertInstanceOf(FieldConfig::class, $field);
+    $this->assertSame($default_mode, $field->getSetting('default_mode'));
+    $this->assertSame($per_page, $field->getSetting('per_page'));
+    $this->assertSame($anonymous, $field->getSetting('anonymous'));
+    $this->assertSame($form_location, $field->getSetting('form_location'));
+    $this->assertSame($preview, $field->getSetting('preview'));
+  }
+
+  /**
+   * Test the migrated field instance values.
+   */
+  public function testCommentFieldInstance() {
+    $this->assertCommentField('page', CommentManagerInterface::COMMENT_MODE_THREADED, 50, 0, FALSE, 1);
+    $this->assertCommentField('story', CommentManagerInterface::COMMENT_MODE_FLAT, 70, 1, FALSE, 0);
+  }
+
+}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldTest.php
new file mode 100644
index 0000000000..dc71a63e3b
--- /dev/null
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentFieldTest.php
@@ -0,0 +1,63 @@
+<?php
+
+namespace Drupal\Tests\comment\Kernel\Migrate\d6;
+
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
+
+/**
+ * Tests the creation of comment fields for each Drupal 6 node type.
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateCommentFieldTest extends MigrateDrupal6TestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['comment', 'menu_ui'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installConfig(['comment']);
+    $this->migrateContentTypes();
+    $this->executeMigrations(['d6_comment_type', 'd6_comment_field']);
+  }
+
+  /**
+   * Asserts the existence of a node comment field.
+   *
+   * @param string $comment_type
+   *   The comment type ID.
+   */
+  protected function assertCommentField($comment_type) {
+    $field = FieldStorageConfig::load("node.$comment_type");
+
+    $this->assertInstanceOf(FieldStorageConfig::class, $field);
+    $this->assertSame('comment', $field->getType());
+    $this->assertSame('node', $field->getTargetEntityTypeId());
+    $this->assertSame($comment_type, $field->getSetting('comment_type'));
+  }
+
+  /**
+   * Tests the creation of a comment field for each node type.
+   */
+  public function testCommentField() {
+    $this->assertCommentField('comment_node_article');
+    $this->assertCommentField('comment_node_company');
+    $this->assertCommentField('comment_node_employee');
+    $this->assertCommentField('comment_node_event');
+    $this->assertCommentField('comment_node_forum');
+    $this->assertCommentField('comment_node_page');
+    $this->assertCommentField('comment_node_sponsor');
+    $this->assertCommentField('comment_node_story');
+    $this->assertCommentField('comment_node_test_event');
+    $this->assertCommentField('comment_node_test_page');
+    $this->assertCommentField('comment_node_test_planet');
+    $this->assertCommentField('comment_node_test_story');
+  }
+
+}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentTypeTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentTypeTest.php
index c28be63b97..339fc5f0d6 100644
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentTypeTest.php
+++ b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentTypeTest.php
@@ -32,10 +32,22 @@ protected function setUp() {
    * Tests the Drupal 6 to Drupal 8 comment type migration.
    */
   public function testCommentType() {
-    $comment_type = CommentType::load('comment');
-    $this->assertIdentical('node', $comment_type->getTargetEntityTypeId());
-    $comment_type = CommentType::load('comment_no_subject');
-    $this->assertIdentical('node', $comment_type->getTargetEntityTypeId());
+    // There should be a comment type for each node type.
+    $comment_types = CommentType::loadMultiple([
+      'comment_node_article',
+      'comment_node_company',
+      'comment_node_employee',
+      'comment_node_event',
+      'comment_node_forum',
+      'comment_node_page',
+      'comment_node_sponsor',
+      'comment_node_story',
+      'comment_node_test_event',
+      'comment_node_test_page',
+      'comment_node_test_planet',
+      'comment_node_test_story',
+    ]);
+    $this->assertCount(12, $comment_types);
   }
 
 }
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityDisplayTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityDisplayTest.php
deleted file mode 100644
index baa28bc549..0000000000
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityDisplayTest.php
+++ /dev/null
@@ -1,39 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Migrate\d6;
-
-use Drupal\Core\Entity\Entity\EntityViewDisplay;
-
-/**
- * Upgrade comment variables to entity.display.node.*.default.yml.
- *
- * @group migrate_drupal_6
- */
-class MigrateCommentVariableEntityDisplayTest extends MigrateCommentVariableDisplayBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['menu_ui'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->executeMigration('d6_comment_entity_display');
-  }
-
-  /**
-   * Tests comment variables migrated into an entity display.
-   */
-  public function testCommentEntityDisplay() {
-    foreach (['page', 'story', 'article'] as $type) {
-      $component = EntityViewDisplay::load('node.' . $type . '.default')->getComponent('comment');
-      $this->assertIdentical('hidden', $component['label']);
-      $this->assertIdentical('comment_default', $component['type']);
-      $this->assertIdentical(20, $component['weight']);
-    }
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplaySubjectTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplaySubjectTest.php
deleted file mode 100644
index 31e61e0a65..0000000000
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplaySubjectTest.php
+++ /dev/null
@@ -1,45 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Migrate\d6;
-
-use Drupal\Core\Entity\Entity\EntityFormDisplay;
-use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
-
-/**
- * Upgrade comment subject variable to core.entity_form_display.comment.*.default.yml
- *
- * @group migrate_drupal_6
- */
-class MigrateCommentVariableEntityFormDisplaySubjectTest extends MigrateDrupal6TestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['comment'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->installConfig(['comment']);
-    $this->executeMigrations([
-      'd6_comment_type',
-      'd6_comment_entity_form_display_subject',
-    ]);
-  }
-
-  /**
-   * Tests comment subject variable migrated into an entity display.
-   */
-  public function testCommentEntityFormDisplay() {
-    $component = EntityFormDisplay::load('comment.comment.default')
-      ->getComponent('subject');
-    $this->assertIdentical('string_textfield', $component['type']);
-    $this->assertIdentical(10, $component['weight']);
-    $component = EntityFormDisplay::load('comment.comment_no_subject.default')
-      ->getComponent('subject');
-    $this->assertNull($component);
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplayTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplayTest.php
deleted file mode 100644
index 818f9b87ea..0000000000
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableEntityFormDisplayTest.php
+++ /dev/null
@@ -1,39 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Migrate\d6;
-
-use Drupal\Core\Entity\Entity\EntityFormDisplay;
-
-/**
- * Upgrade comment variables to core.entity_form_display.node.*.default.yml.
- *
- * @group migrate_drupal_6
- */
-class MigrateCommentVariableEntityFormDisplayTest extends MigrateCommentVariableDisplayBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['menu_ui'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->executeMigration('d6_comment_entity_form_display');
-  }
-
-  /**
-   * Tests comment variables migrated into an entity display.
-   */
-  public function testCommentEntityFormDisplay() {
-    foreach (['page', 'article', 'story'] as $type) {
-      $component = EntityFormDisplay::load('node.' . $type . '.default')
-        ->getComponent('comment');
-      $this->assertIdentical('comment_default', $component['type']);
-      $this->assertIdentical(20, $component['weight']);
-    }
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableFieldTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableFieldTest.php
deleted file mode 100644
index e2a2189559..0000000000
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableFieldTest.php
+++ /dev/null
@@ -1,37 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Migrate\d6;
-
-use Drupal\field\Entity\FieldStorageConfig;
-use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
-
-/**
- * Upgrade comment variables to field.storage.node.comment.yml.
- *
- * @group migrate_drupal_6
- */
-class MigrateCommentVariableFieldTest extends MigrateDrupal6TestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['comment', 'menu_ui'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->installConfig(['comment']);
-    $this->migrateContentTypes();
-    $this->executeMigrations(['d6_comment_type', 'd6_comment_field']);
-  }
-
-  /**
-   * Tests comment variables migrated into a field entity.
-   */
-  public function testCommentField() {
-    $this->assertTrue(is_object(FieldStorageConfig::load('node.comment')));
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableInstanceTest.php b/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableInstanceTest.php
deleted file mode 100644
index 90b256fb14..0000000000
--- a/core/modules/comment/tests/src/Kernel/Migrate/d6/MigrateCommentVariableInstanceTest.php
+++ /dev/null
@@ -1,60 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Migrate\d6;
-
-use Drupal\comment\CommentManagerInterface;
-use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
-use Drupal\node\Entity\Node;
-
-/**
- * Upgrade comment variables to field.instance.node.*.comment.yml.
- *
- * @group migrate_drupal_6
- */
-class MigrateCommentVariableInstanceTest extends MigrateDrupal6TestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['comment', 'menu_ui'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-    $this->installConfig(['comment']);
-    $this->migrateContentTypes();
-    $this->executeMigrations([
-      'd6_comment_type',
-      'd6_comment_field',
-      'd6_comment_field_instance',
-    ]);
-  }
-
-  /**
-   * Test the migrated field instance values.
-   */
-  public function testCommentFieldInstance() {
-    $node = Node::create(['type' => 'page']);
-    $this->assertIdentical(0, $node->comment->status);
-    $this->assertIdentical('comment', $node->comment->getFieldDefinition()->getName());
-    $settings = $node->comment->getFieldDefinition()->getSettings();
-    $this->assertIdentical(CommentManagerInterface::COMMENT_MODE_THREADED, $settings['default_mode']);
-    $this->assertIdentical(50, $settings['per_page']);
-    $this->assertFalse($settings['anonymous']);
-    $this->assertFalse($settings['form_location']);
-    $this->assertTrue($settings['preview']);
-
-    $node = Node::create(['type' => 'story']);
-    $this->assertIdentical(2, $node->comment_no_subject->status);
-    $this->assertIdentical('comment_no_subject', $node->comment_no_subject->getFieldDefinition()->getName());
-    $settings = $node->comment_no_subject->getFieldDefinition()->getSettings();
-    $this->assertIdentical(CommentManagerInterface::COMMENT_MODE_FLAT, $settings['default_mode']);
-    $this->assertIdentical(70, $settings['per_page']);
-    $this->assertTrue($settings['anonymous']);
-    $this->assertFalse($settings['form_location']);
-    $this->assertFalse($settings['preview']);
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariablePerCommentTypeTest.php b/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariablePerCommentTypeTest.php
deleted file mode 100644
index dd1b1fd06c..0000000000
--- a/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariablePerCommentTypeTest.php
+++ /dev/null
@@ -1,62 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Plugin\migrate\source\d6;
-
-use Drupal\Tests\migrate\Kernel\MigrateSqlSourceTestBase;
-
-/**
- * Tests comment variable per comment type source plugin.
- *
- * @covers \Drupal\comment\Plugin\migrate\source\d6\CommentVariablePerCommentType
- * @group comment
- */
-class CommentVariablePerCommentTypeTest extends MigrateSqlSourceTestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['comment', 'migrate_drupal'];
-
-  /**
-   * {@inheritdoc}
-   */
-  public function providerSource() {
-    $tests = [];
-
-    // The source data.
-    $tests[0]['source_data']['node_type'] = [
-      [
-        'type' => 'page',
-      ],
-      [
-        'type' => 'story',
-      ],
-    ];
-
-    $tests[0]['source_data']['variable'] = [
-      [
-        'name' => 'comment_subject_field_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_subject_field_story',
-        'value' => serialize(0),
-      ],
-    ];
-
-    // The expected results.
-    // Each result will also include a label and description, but those are
-    // static values set by the source plugin and don't need to be asserted.
-    $tests[0]['expected_data'] = [
-      [
-        'comment_type' => 'comment',
-      ],
-      [
-        'comment_type' => 'comment_no_subject',
-      ],
-    ];
-
-    return $tests;
-  }
-
-}
diff --git a/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariableTest.php b/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariableTest.php
deleted file mode 100644
index a84c776b77..0000000000
--- a/core/modules/comment/tests/src/Kernel/Plugin/migrate/source/d6/CommentVariableTest.php
+++ /dev/null
@@ -1,92 +0,0 @@
-<?php
-
-namespace Drupal\Tests\comment\Kernel\Plugin\migrate\source\d6;
-
-use Drupal\Tests\migrate\Kernel\MigrateSqlSourceTestBase;
-
-/**
- * Tests d6_comment_variable source plugin.
- *
- * @covers \Drupal\comment\Plugin\migrate\source\d6\CommentVariable
- * @group comment
- */
-class CommentVariableTest extends MigrateSqlSourceTestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static $modules = ['comment', 'migrate_drupal'];
-
-  /**
-   * {@inheritdoc}
-   */
-  public function providerSource() {
-    $tests = [];
-
-    // The source data.
-    $tests[0]['source_data']['node_type'] = [
-      [
-        'type' => 'page',
-      ],
-    ];
-
-    $tests[0]['source_data']['variable'] = [
-      [
-        'name' => 'comment_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_default_mode_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_default_order_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_default_per_page_page',
-        'value' => serialize(50),
-      ],
-      [
-        'name' => 'comment_controls_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_anonymous_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_subject_field_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_preview_page',
-        'value' => serialize(1),
-      ],
-      [
-        'name' => 'comment_form_location_page',
-        'value' => serialize(1),
-      ],
-    ];
-
-    // The expected results.
-    $tests[0]['expected_data'] = [
-      [
-        'comment' => '1',
-        'comment_default_mode' => '1',
-        'comment_default_order' => '1',
-        'comment_default_per_page' => '50',
-        'comment_controls' => '1',
-        'comment_anonymous' => '1',
-        'comment_subject_field' => '1',
-        'comment_preview' => '1',
-        'comment_form_location' => '1',
-        'node_type' => 'page',
-        'comment_type' => 'comment',
-      ],
-    ];
-
-    return $tests;
-  }
-
-}
diff --git a/core/modules/node/src/Plugin/migrate/source/d6/NodeType.php b/core/modules/node/src/Plugin/migrate/source/d6/NodeType.php
index b5a66ce7e2..1176b38c60 100644
--- a/core/modules/node/src/Plugin/migrate/source/d6/NodeType.php
+++ b/core/modules/node/src/Plugin/migrate/source/d6/NodeType.php
@@ -62,7 +62,7 @@ public function query() {
    * {@inheritdoc}
    */
   public function fields() {
-    return [
+    $fields = [
       'type' => $this->t('Machine name of the node type.'),
       'name' => $this->t('Human name of the node type.'),
       'module' => $this->t('The module providing the node type.'),
@@ -78,6 +78,30 @@ public function fields() {
       'orig_type' => $this->t('The original type.'),
       'teaser_length' => $this->t('Teaser length'),
     ];
+    if ($this->moduleExists('comment')) {
+      $fields += $this->getCommentFields();
+    }
+    return $fields;
+  }
+
+  /**
+   * Returns the fields containing comment settings for each node type.
+   *
+   * @return string[]
+   *   An associative array of field descriptions, keyed by field.
+   */
+  protected function getCommentFields() {
+    return [
+      'comment' => $this->t('Default comment setting'),
+      'comment_default_mode' => $this->t('Default display mode'),
+      'comment_default_order' => $this->t('Default display order'),
+      'comment_default_per_page' => $this->t('Default comments per page'),
+      'comment_controls' => $this->t('Comment controls'),
+      'comment_anonymous' => $this->t('Anonymous commenting'),
+      'comment_subject_field' => $this->t('Comment subject field'),
+      'comment_preview' => $this->t('Preview comment'),
+      'comment_form_location' => $this->t('Location of comment submission form'),
+    ];
   }
 
   /**
@@ -111,6 +135,13 @@ public function prepareRow(Row $row) {
       $row->setSourceProperty('available_menus', [$default_node_menu]);
       $row->setSourceProperty('parent', $default_node_menu . ':');
     }
+
+    if ($this->moduleExists('comment')) {
+      foreach (array_keys($this->getCommentFields()) as $field) {
+        $row->setSourceProperty($field, $this->variableGet($field . '_' . $type, NULL));
+      }
+    }
+
     return parent::prepareRow($row);
   }