diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 2786774..dcb9236 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -2092,19 +2092,6 @@ function template_preprocess_field(&$variables, $hook) {
   // readers.
   $variables['label'] = String::checkPlain($element['#title']);
 
-  // We want other preprocess functions and the theme implementation to have
-  // fast access to the field item render arrays. The item render array keys
-  // (deltas) should always be numerically indexed starting from 0, and looping
-  // on those keys is faster than calling
-  // \Drupal\Core\Render\Element::children() or looping on all keys within
-  // $element, since that requires traversal of all element properties.
-  $variables['items'] = array();
-  $delta = 0;
-  while (!empty($element[$delta])) {
-    $variables['items'][$delta] = $element[$delta];
-    $delta++;
-  }
-
   // Add default CSS classes. Since there can be many fields rendered on a page,
   // save some overhead by calling strtr() directly instead of
   // drupal_html_class().
@@ -2118,6 +2105,7 @@ function template_preprocess_field(&$variables, $hook) {
     'field-type-' . $variables['field_type_css'],
     'field-label-' . $element['#label_display'],
   );
+
   // Add a "clearfix" class to the wrapper since we float the label and the
   // field items in field.module.css if the label is inline.
   if ($element['#label_display'] == 'inline') {
@@ -2134,15 +2122,26 @@ function template_preprocess_field(&$variables, $hook) {
     $default_attributes = new Attribute;
   }
 
-  // Modules (e.g., rdf.module) can add field item attributes (to
-  // $item->_attributes) within hook_entity_prepare_view(). Some field
-  // formatters move those attributes into some nested formatter-specific
-  // element in order have them rendered on the desired HTML element (e.g., on
-  // the <a> element of a field item being rendered as a link). Other field
-  // formatters leave them within $element['#items'][$delta]['_attributes'] to
-  // be rendered on the item wrappers provided by field.html.twig.
-  foreach ($variables['items'] as $delta => $item) {
-    $variables['item_attributes'][$delta] = !empty($element['#items'][$delta]->_attributes) ? new Attribute($element['#items'][$delta]->_attributes) : clone($default_attributes);
+  // We want other preprocess functions and the theme implementation to have
+  // fast access to the field item render arrays. The item render array keys
+  // (deltas) should always be numerically indexed starting from 0, and looping
+  // on those keys is faster than calling element_children() or looping on all
+  // keys within $element, since that requires traversal of all element
+  // properties.
+  $variables['items'] = array();
+  $delta = 0;
+  while (!empty($element[$delta])) {
+    $variables['items'][$delta]['value'] = $element[$delta];
+
+    // Modules (e.g., rdf.module) can add field item attributes (to
+    // $item->_attributes) within hook_entity_prepare_view(). Some field
+    // formatters move those attributes into some nested formatter-specific
+    // element in order have them rendered on the desired HTML element (e.g., on
+    // the <a> element of a field item being rendered as a link). Other field
+    // formatters leave them within $element['#items'][$delta]['_attributes'] to
+    // be rendered on the item wrappers provided by field.html.twig.
+    $variables['items'][$delta]['attributes'] = !empty($element['#items'][$delta]->_attributes) ? new Attribute($element['#items'][$delta]->_attributes) : clone($default_attributes);
+    $delta++;
   }
 }
 
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index dbe3bee..6ab7692 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -868,7 +868,7 @@ function comment_preprocess_field(&$variables) {
     $variables['title_attributes']['class'][] = 'title';
 
     // Append additional attributes (eg. RDFa) from the first field item.
-    $variables['attributes'] += $variables['item_attributes'][0]->storage();
+    $variables['attributes'] += $variables['items'][0]['attributes']->storage();
 
     // Create separate variables for the comments and comment form.
     $variables['comments'] = $element[0]['comments'];
diff --git a/core/modules/node/templates/field--node--title.html.twig b/core/modules/node/templates/field--node--title.html.twig
index 25432c0..8051544 100644
--- a/core/modules/node/templates/field--node--title.html.twig
+++ b/core/modules/node/templates/field--node--title.html.twig
@@ -8,11 +8,17 @@
  *
  * Available variables:
  * - attributes: HTML attributes for the containing span element.
- * - items: List of all the field items.
+ * - items: List of all the field items. Each item contains:
+ *   - attributes: List of HTML attributes for each item.
+ *   - value: The field item value.
  *
  * @see field.html.twig
  *
  * @ingroup themeable
  */
 #}
-<span{{ attributes }}>{{ items }}</span>
+<span{{ attributes }}>
+  {%- for item in items -%}
+    {{ item.value }}
+  {%- endfor -%}
+</span>
diff --git a/core/modules/system/templates/field.html.twig b/core/modules/system/templates/field.html.twig
index d38b028..559af33f 100644
--- a/core/modules/system/templates/field.html.twig
+++ b/core/modules/system/templates/field.html.twig
@@ -21,8 +21,9 @@
  * - title_attributes: HTML attributes for the title.
  * - label: The label for the field.
  * - content_attributes: HTML attributes for the content.
- * - items: List of all the field items.
- * - item_attributes: List of HTML attributes for each item.
+ * - items: List of all the field items. Each item contains:
+ *   - attributes: List of HTML attributes for each item.
+ *   - value: The field item's value.
  *
  * @see template_preprocess_field()
  *
@@ -31,11 +32,11 @@
 #}
 <div{{ attributes }}>
   {% if not label_hidden %}
-    <div class="field-label{% if title_attributes.class %} {{ title_attributes.class }}{% endif %}"{{ title_attributes|without('class') }}>{{ label }}:&nbsp;</div>
+    <div{{ title_attributes.addClass('field-label') }}>{{ label }}:&nbsp;</div>
   {% endif %}
-  <div class="field-items"{{ content_attributes }}>
-    {% for delta, item in items %}
-      <div class="field-item"{{ item_attributes[delta] }}>{{ item }}</div>
+  <div{{ content_attributes.addClass('field-items') }}>
+    {% for item in items %}
+      <div{{ item.attributes.addClass('field-item') }}>{{ item.value }}</div>
     {% endfor %}
   </div>
 </div>
diff --git a/core/themes/bartik/templates/field--taxonomy-term-reference.html.twig b/core/themes/bartik/templates/field--taxonomy-term-reference.html.twig
index 4c579ee..a818519 100644
--- a/core/themes/bartik/templates/field--taxonomy-term-reference.html.twig
+++ b/core/themes/bartik/templates/field--taxonomy-term-reference.html.twig
@@ -9,20 +9,21 @@
  * - title_attributes: HTML attributes for the label.
  * - label: The label for the field.
  * - content_attributes: HTML attributes for the content.
- * - items: List of all the field items.
- * - item_attributes: List of HTML attributes for each item.
+ * - items: List of all the field items. Each item contains:
+ *   - attributes: List of HTML attributes for each item.
+ *   - value: The field item's value.
  *
  * @see template_preprocess_field()
  * @see bartik_preprocess_field()
  */
 #}
-<div class="{{ attributes.class }} clearfix"{{ attributes|without('class') }}>
+<div{{ attributes.addClass('clearfix') }}>
   {% if not label_hidden %}
     <h3{{ title_attributes }}>{{ label }}: </h3>
   {% endif %}
-  <ul class="links field-items {{ content_attributes.class }}"{{ content_attributes|without('class') }}>
+  <ul{{ content_attributes.addClass('links', 'field-items') }}>
     {% for delta, item in items %}
-      <li class="taxonomy-term-reference-{{ delta }}"{{ item_attributes[delta] }}>{{ item }}</li>
+      <li{{ item.attributes }}>{{ item.value }}</li>
     {% endfor %}
   </ul>
 </div>