diff --git a/core/lib/Drupal/Core/Entity/EntityFormController.php b/core/lib/Drupal/Core/Entity/EntityFormController.php
index 372bf35..e4acf56 100644
--- a/core/lib/Drupal/Core/Entity/EntityFormController.php
+++ b/core/lib/Drupal/Core/Entity/EntityFormController.php
@@ -186,12 +186,16 @@ public function processForm($element, $form_state, $form) {
       }
     }
 
-    // Hide extra fields.
+    // Hide or assign weights for extra fields.
     $extra_fields = field_info_extra_fields($this->entity->entityType(), $this->entity->bundle(), 'form');
     foreach ($extra_fields as $extra_field => $info) {
-      if (!$this->getFormDisplay($form_state)->getComponent($extra_field)) {
+      $component = $this->getFormDisplay($form_state)->getComponent($extra_field);
+      if (!$component) {
         $element[$extra_field]['#access'] = FALSE;
       }
+      else {
+        $element[$extra_field]['#weight'] = $component['weight'];
+      }
     }
 
     return $element;
diff --git a/core/modules/comment/lib/Drupal/comment/CommentFormController.php b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
index ad4b9a0..6503a3a 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentFormController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
@@ -46,9 +46,7 @@ public function form(array $form, array &$form_state) {
       $form += $form_state['comment_preview'];
     }
 
-    $form['author'] = array(
-      '#weight' => 10,
-    );
+    $form['author'] = array();
     // Display author information in a details element for comment moderators.
     if ($is_admin) {
       $form['author'] += array(
diff --git a/core/modules/field/lib/Drupal/field/FieldInfo.php b/core/modules/field/lib/Drupal/field/FieldInfo.php
index 2639c25..f791af8 100644
--- a/core/modules/field/lib/Drupal/field/FieldInfo.php
+++ b/core/modules/field/lib/Drupal/field/FieldInfo.php
@@ -538,12 +538,12 @@ public function getBundleExtraFields($entity_type, $bundle) {
     // Cache miss: read from hook_field_extra_fields(). Note: given the current
     // shape of the hook, we have no other way than collecting extra fields on
     // all bundles.
-    $info = array();
+    $info = array('form' => array(), 'display' => array());
     $extra = $this->moduleHandler->invokeAll('field_extra_fields');
     drupal_alter('field_extra_fields', $extra);
-    // Merge in saved settings.
+
     if (isset($extra[$entity_type][$bundle])) {
-      $info = $this->prepareExtraFields($extra[$entity_type][$bundle], $entity_type, $bundle);
+      $info += $extra[$entity_type][$bundle];
     }
 
     // Store in the 'static' and persistent caches.
@@ -593,38 +593,4 @@ public function prepareInstance($instance, $field_type) {
     return $instance;
   }
 
-  /**
-   * Prepares 'extra fields' for the current run-time context.
-   *
-   * @param $extra_fields
-   *   The array of extra fields, as collected in hook_field_extra_fields().
-   * @param $entity_type
-   *   The entity type.
-   * @param $bundle
-   *   The bundle name.
-   *
-   * @return
-   *   The list of extra fields completed for the current runtime context.
-   */
-  public function prepareExtraFields($extra_fields, $entity_type, $bundle) {
-    $entity_type_info = entity_get_info($entity_type);
-    $bundle_settings = field_bundle_settings($entity_type, $bundle);
-    $extra_fields += array('form' => array(), 'display' => array());
-
-    $result = array();
-    // Extra fields in forms.
-    foreach ($extra_fields['form'] as $name => $field_data) {
-      $settings = isset($bundle_settings['extra_fields']['form'][$name]) ? $bundle_settings['extra_fields']['form'][$name] : array();
-      if (isset($settings['weight'])) {
-        $field_data['weight'] = $settings['weight'];
-      }
-      $result['form'][$name] = $field_data;
-    }
-
-    // Extra fields in displayed entities.
-    $result['display'] = $extra_fields['display'];
-
-    return $result;
-  }
-
 }