config/packages/asset_mapper.php

@@ -1,21 +1,19 @@
 <?php declare(strict_types=1);
 
 use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;
+use Symfony\Config\FrameworkConfig;
 
-return static function (ContainerConfigurator $containerConfigurator): void {
-    $containerConfigurator->extension('framework', [
-        'asset_mapper' => [
-            'paths' => [
-                'assets/',
-            ],
-            'missing_import_mode' => 'strict',
-        ],
-    ]);
+return static function (
+    ContainerConfigurator $containerConfigurator,
+    FrameworkConfig $frameworkConfig,
+): void {
+    $frameworkConfig->assetMapper()
+        ->path('assets/', true)
+        ->missingImportMode('strict')
+        ->importmapPolyfill(false)
+    ;
     if ($containerConfigurator->env() === 'prod') {
-        $containerConfigurator->extension('framework', [
-            'asset_mapper' => [
-                'missing_import_mode' => 'warn',
-            ],
-        ]);
+        $frameworkConfig->assetMapper()
+            ->missingImportMode('warn');
     }
 };