Er is onverwacht een fout opgetreden. Probeer het later nog eens.

Drupal\Core\Asset\Exception\InvalidLibrariesExtendSpecificationException: The specified library "classy/file" does not exist. in Drupal\Core\Asset\LibraryDiscoveryCollector->applyLibrariesExtend() (line 154 of core/lib/Drupal/Core/Asset/LibraryDiscoveryCollector.php).
Drupal\Core\Asset\LibraryDiscoveryCollector->getLibraryDefinitions('file') (Line: 66)
Drupal\Core\Asset\LibraryDiscoveryCollector->resolveCacheMiss('file') (Line: 149)
Drupal\Core\Cache\CacheCollector->get('file') (Line: 44)
Drupal\Core\Asset\LibraryDiscovery->getLibrariesByExtension('file') (Line: 58)
Drupal\Core\Asset\LibraryDiscovery->getLibraryByName('file', 'drupal.file') (Line: 68)
Drupal\Core\Asset\LibraryDependencyResolver->doGetDependencies(Array, Array) (Line: 70)
Drupal\Core\Asset\LibraryDependencyResolver->doGetDependencies(Array) (Line: 41)
Drupal\Core\Asset\LibraryDependencyResolver->getLibrariesWithDependencies(Array) (Line: 87)
Drupal\Core\Asset\LibraryDependencyResolver->getMinimalRepresentativeSubset(Array) (Line: 112)
Drupal\Core\Asset\AssetResolver->getLibrariesToLoad(Object) (Line: 130)
Drupal\Core\Asset\AssetResolver->getCssAssets(Object, 1, Object) (Line: 320)
Drupal\Core\Render\HtmlResponseAttachmentsProcessor->processAssetLibraries(Object, Array) (Line: 164)
Drupal\Core\Render\HtmlResponseAttachmentsProcessor->processAttachments(Object) (Line: 45)
Drupal\Core\EventSubscriber\HtmlResponseSubscriber->onRespond(Object, 'kernel.response', Object)
call_user_func(Array, Object, 'kernel.response', Object) (Line: 111)
Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.response') (Line: 214)
Symfony\Component\HttpKernel\HttpKernel->filterResponse(Object, Object, 1) (Line: 160)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 191)
Drupal\page_cache\StackMiddleware\PageCache->fetch(Object, 1, 1) (Line: 128)
Drupal\page_cache\StackMiddleware\PageCache->lookup(Object, 1, 1) (Line: 82)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 704)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)