Captcha disappears

src/Element/Captcha.php

@@ -91,7 +91,9 @@ class Captcha extends FormElement implements ContainerFactoryPluginInterface {
     // Add JavaScript for general CAPTCHA functionality.
     $element['#attached']['library'][] = 'captcha/base';
 
-    if ($form_state->getTriggeringElement() && isset($form_state->getTriggeringElement()['#limit_validation_errors']) && is_array($form_state->getTriggeringElement()['#limit_validation_errors'])) {
+    $triggering_element = $form_state->getTriggeringElement();
+    $recalculate = !empty($triggering_element['#recalculate']);
+    if ($triggering_element && isset($triggering_element['#limit_validation_errors']) && is_array($triggering_element['#limit_validation_errors']) && !$recalculate) {
       // This is a partial (ajax) submission with limited validation. Do not
       // change anything about the captcha element, assume that it will not
       // update the captcha element, do not generate anything, which keeps the