refine as per feedback

Author: PhilETaylor

src/DependencyInjection/Configuration.php

@@ -34,7 +34,9 @@ public function getConfigTreeBuilder()
                     ->isRequired()
                     ->info('The path where Encore is building the assets - i.e. Encore.setOutputPath()')
                 ->end()
-                ->scalarNode('crossorigin')
+                ->enumNode('crossorigin')
+                    ->defaultValue('anonymous')
+                    ->values(['anonymous', 'use-credentials'])
                     ->info('crossorigin value when Encore.enableIntegrityHashes is used, can be anonymous (default) or use-credentials')
                 ->end()
                 ->booleanNode('cache')

src/DependencyInjection/WebpackEncoreExtension.php

@@ -53,7 +53,7 @@ public function load(array $configs, ContainerBuilder $container)
         $container->setAlias(EntrypointLookupInterface::class, new Alias($this->getEntrypointServiceId('_default')));
 
         $container->getDefinition('webpack_encore.tag_renderer')
-            ->replaceArgument(2, $config['crossorigin']??'anonymous');
+            ->replaceArgument(2, $config['crossorigin']);
     }
 
     private function entrypointFactory(ContainerBuilder $container, string $name, string $path, bool $cacheEnabled): Reference

src/Resources/config/services.xml

@@ -16,7 +16,7 @@
         <service id="webpack_encore.tag_renderer" class="Symfony\WebpackEncoreBundle\Asset\TagRenderer">
             <argument type="service" id="webpack_encore.entrypoint_lookup_collection" />
             <argument type="service" id="assets.packages" />
-            <argument type="string" id="webpack_encore.crossorigin" />
+            <argument>anonymous</argument>
         </service>
 
         <service id="webpack_encore.twig_entry_files_extension" class="Symfony\WebpackEncoreBundle\Twig\EntryFilesTwigExtension">