diff --git a/core/lib/Drupal/Core/Asset/AssetResolver.php b/core/lib/Drupal/Core/Asset/AssetResolver.php
index 3ffd7a9..003d88c 100644
--- a/core/lib/Drupal/Core/Asset/AssetResolver.php
+++ b/core/lib/Drupal/Core/Asset/AssetResolver.php
@@ -285,7 +285,7 @@ public function getJsAssets(AttachedAssetsInterface $assets, $optimize) {
       $js_assets_header = [];
       $js_assets_footer = [];
       foreach ($javascript as $key => $item) {
-        if ($item['scope'] == 'header' && $item['type'] !== 'setting') {
+        if ($item['scope'] == 'header') {
           $js_assets_header[$key] = $item;
         }
         elseif ($item['scope'] == 'footer') {
@@ -295,9 +295,7 @@ public function getJsAssets(AttachedAssetsInterface $assets, $optimize) {
 
       if ($optimize) {
         $collection_optimizer = \Drupal::service('asset.js.collection_optimizer');
-        if ($js_assets_header) {
-          $js_assets_header = $collection_optimizer->optimize($js_assets_header);
-        }
+        $js_assets_header = $collection_optimizer->optimize($js_assets_header);
         $js_assets_footer = $collection_optimizer->optimize($js_assets_footer);
       }
 
diff --git a/core/lib/Drupal/Core/Asset/JsCollectionGrouper.php b/core/lib/Drupal/Core/Asset/JsCollectionGrouper.php
index 710e3c0..2b38d6d 100644
--- a/core/lib/Drupal/Core/Asset/JsCollectionGrouper.php
+++ b/core/lib/Drupal/Core/Asset/JsCollectionGrouper.php
@@ -45,6 +45,9 @@ public function group(array $js_assets) {
           // Do not group external items.
           $group_keys = FALSE;
           break;
+        default:
+          $e = new \Exception();
+          trigger_error($e->getTraceAsString());
       }
 
       // If the group keys don't match the most recent group we're working with,
diff --git a/core/lib/Drupal/Core/Asset/JsCollectionOptimizer.php b/core/lib/Drupal/Core/Asset/JsCollectionOptimizer.php
index d636a4d..4aa4383 100644
--- a/core/lib/Drupal/Core/Asset/JsCollectionOptimizer.php
+++ b/core/lib/Drupal/Core/Asset/JsCollectionOptimizer.php
@@ -53,6 +53,7 @@ public function optimize(array $js_assets) {
     $key = $this->generateHash($js_groups);
 
     $js_assets = array();
+    $libraries = [];
     foreach ($js_groups as $order => $js_group) {
       // We have to return a single asset, not a group of assets. It is now up
       // to one of the pieces of code in the switch statement below to set the
@@ -85,6 +86,9 @@ public function optimize(array $js_assets) {
           $uri = $js_group['items'][0]['data'];
           $js_assets[$order]['data'] = $uri;
           break;
+        case 'setting':
+          $js_assets[$order]['data'] = $js_group['data'];
+          break;
       }
     }
     if ($libraries) {
diff --git a/core/modules/system/src/Controller/CssAssetController.php b/core/modules/system/src/Controller/CssAssetController.php
index 8796880..8f1b0b5 100644
--- a/core/modules/system/src/Controller/CssAssetController.php
+++ b/core/modules/system/src/Controller/CssAssetController.php
@@ -46,7 +46,7 @@ protected function getKeyAndGroup(AttachedAssetsInterface $attached_assets, $gro
 
     // Group the assets.
     $groups = $this->grouper->group($assets);
-    if (!isset($groups[$group_delta]['preprocess'])) {
+    if (!isset($groups[$group_delta])) {
       throw new BadRequestHttpException('Invalid filename.');
     }
     $group = $groups[$group_delta];
diff --git a/core/modules/system/src/Controller/JsAssetController.php b/core/modules/system/src/Controller/JsAssetController.php
index de6a142..4fdf401 100644
--- a/core/modules/system/src/Controller/JsAssetController.php
+++ b/core/modules/system/src/Controller/JsAssetController.php
@@ -54,14 +54,10 @@ protected function getKeyAndGroup(AttachedAssetsInterface $attached_assets, $gro
     $assets = $scope == 'header' ? $js_assets_header : $js_assets_footer;
     // While the asset resolver will find setting, these are never aggregated,
     // so filter them out. Settings are always in the header.
-    if ($scope == 'header') {
-      $assets = array_filter($assets, function($item) {
-        return $item['type'] !== 'setting';
-      });
-    }
+    unset($assets['drupalSettings']);
     // Group the assets.
     $groups = $this->grouper->group($assets);
-    if (!isset($groups[$group_delta]['preprocess'])) {
+    if (!isset($groups[$group_delta])) {
       throw new BadRequestHttpException('Invalid filename.');
     }
     $group = $groups[$group_delta];