diff -u b/recaptcha.module b/recaptcha.module
--- b/recaptcha.module
+++ b/recaptcha.module
@@ -87,6 +87,7 @@
             'data-size' => $config->get('widget.size'),
             'data-tabindex' => $config->get('widget.tabindex'),
           ];
+          $captcha['form']['#attached']['library'][] = 'recaptcha/recaptcha';
 
           // Set the callback for invisible captcha.
           if ('invisible' === $config->get('widget.size')) {
@@ -121,9 +122,6 @@
                   'recaptcha_api',
                 ],
               ],
-              'library' => [
-                'recaptcha/recaptcha',
-              ],
             ],
           ];
         }