diff -u b/core/modules/auto_updates/src/ReadinessChecker/FileSystemBase.php b/core/modules/auto_updates/src/ReadinessChecker/FileSystemBase.php
--- b/core/modules/auto_updates/src/ReadinessChecker/FileSystemBase.php
+++ b/core/modules/auto_updates/src/ReadinessChecker/FileSystemBase.php
@@ -35,7 +35,7 @@
     if (!file_exists(implode(DIRECTORY_SEPARATOR, [$this->getRootPath(), 'core', 'core.api.php']))) {
       $messages[] = $this->t('The web root could not be located.');
     }
-    if (!file_exists($this->getVendorPath() . DIRECTORY_SEPARATOR .  'autoload.php')) {
+    if (!file_exists($this->getVendorPath() . DIRECTORY_SEPARATOR . 'autoload.php')) {
       $messages[] = $this->t('Vendor folder "@vendor" is not a valid directory. Alternate vendor folder locations are not currently supported.', [
         '@vendor' => $this->getVendorPath(),
       ]);