diff --git a/core/misc/autocomplete.js b/core/misc/autocomplete.js
index 7dc2c39..7a9e0e0 100644
--- a/core/misc/autocomplete.js
+++ b/core/misc/autocomplete.js
@@ -71,6 +71,12 @@ function searchHandler (event) {
  * @param {Function} response
  */
 function sourceData (request, response) {
+  var elementId = this.element.attr('id');
+
+  if (!(elementId in autocomplete.cache)) {
+    autocomplete.cache[elementId] = {};
+  }
+
   /**
    * Filter through the suggestions removing all terms already tagged and
    * display the available terms to the user.
@@ -94,25 +100,18 @@ function sourceData (request, response) {
    * @param {Object} data
    */
   function sourceCallbackHandler (data) {
-    // Drupal returns an object, we need an array.
-    var terms = [];
-    for (var i in data) {
-      if (data.hasOwnProperty(i)) {
-        terms.push(data[i]);
-      }
-    }
-    autocomplete.cache[term] = terms;
+    autocomplete.cache[elementId][term] = data;
 
     // Send the new string array of terms to the jQuery UI list.
-    showSuggestions(terms);
+    showSuggestions(data);
   }
 
   // Get the desired term and construct the autocomplete URL for it.
   var term = autocomplete.extractLastTerm(request.term);
 
   // Check if the term is already cached.
-  if (autocomplete.cache.hasOwnProperty(term)) {
-    showSuggestions(autocomplete.cache[term]);
+  if (autocomplete.cache[elementId].hasOwnProperty(term)) {
+    showSuggestions(autocomplete.cache[elementId][term]);
   }
   else {
     var options = $.extend({ success: sourceCallbackHandler, data: { q: term } }, autocomplete.ajax);
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/EntityReferenceAutocomplete.php b/core/modules/entity_reference/lib/Drupal/entity_reference/EntityReferenceAutocomplete.php
index 8fa080c..ac84c9e 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/EntityReferenceAutocomplete.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/EntityReferenceAutocomplete.php
@@ -100,7 +100,7 @@ public function getMatches($field, $instance, $entity_type, $entity_id = '', $pr
           if (strpos($key, ',') !== FALSE || strpos($key, '"') !== FALSE) {
             $key = '"' . str_replace('"', '""', $key) . '"';
           }
-          $matches[$prefix . $key] = $label;
+          $matches[] = array('value' => $prefix . $key, 'label' => $label);
         }
       }
     }
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Controller/TermAutocompleteController.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Controller/TermAutocompleteController.php
index 616091e..1c12516 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Controller/TermAutocompleteController.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Controller/TermAutocompleteController.php
@@ -200,7 +200,7 @@ protected function getMatchingTerms($tags_typed, array $vids, $tag_last) {
         if (strpos($name, ',') !== FALSE || strpos($name, '"') !== FALSE) {
           $name = '"' . str_replace('"', '""', $name) . '"';
         }
-        $matches[$prefix . $name] = String::checkPlain($term->label());
+        $matches[] = array('value' => $prefix . $name, 'label' => String::checkPlain($term->label()));
       }
       return $matches;
     }
diff --git a/core/modules/user/lib/Drupal/user/UserAutocomplete.php b/core/modules/user/lib/Drupal/user/UserAutocomplete.php
index 4d36923..a7a20b2 100644
--- a/core/modules/user/lib/Drupal/user/UserAutocomplete.php
+++ b/core/modules/user/lib/Drupal/user/UserAutocomplete.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\user;
 
+use Drupal\Component\Utility\String;
 use Drupal\Core\Config\ConfigFactory;
 use Drupal\Core\Database\Connection;
 
@@ -62,12 +63,12 @@ public function getMatches($string, $include_anonymous = FALSE) {
         $anonymous_name = $this->configFactory->get('user.settings')->get('anonymous');
         // Allow autocompletion for the anonymous user.
         if (stripos($anonymous_name, $string) !== FALSE) {
-          $matches[$anonymous_name] = check_plain($anonymous_name);
+          $matches[] = array('value' => $anonymous_name, 'label' => String::checkPlain($anonymous_name));
         }
       }
       $result = $this->connection->select('users')->fields('users', array('name'))->condition('name', db_like($string) . '%', 'LIKE')->range(0, 10)->execute();
       foreach ($result as $account) {
-        $matches[$account->name] = check_plain($account->name);
+        $matches[] = array('value' => $account->name, 'label' => String::checkPlain($account->name));
       }
     }