--- /dev/null
+<?php
+
+/**
+ * @file
+ * Post update functions for Contact.
+ */
+
+use Drupal\contact\Entity\ContactForm;
+
+
+/**
+ * Initialize 'message' and 'redirect' field values to 'contact_form' entities.
+ */
+function contact_post_update_add_message_redirect_field_to_contact_form() {
+ /** @var \Drupal\contact\ContactFormInterface $contact */
+ foreach (ContactForm::loadMultiple() as $contact) {
+ $contact
+ ->setMessage('Your message has been sent.')
+ ->setRedirectPath('')
+ ->save();
+ }
+}