Issue sending emails from a contact form

Contact forms contain by default two fields named "sender name" and "sender email".
The problem is caused by the fact that i disabled those fields in my form (instead of the "sender name" field, i added two separated fields for "name" and "last name").
As a result, the contact form module is passing an empty sender of type AccountInterface.
This used to work with the old swift_mailer module, that used the website default email address as a fallback.

Right now i patched the problem by forcing symfony mailer to use the website default email address as the sender:

--- Address.php.bak     2024-04-03 08:42:11.564698369 +0000
+++ Address.php 2024-04-03 08:42:38.244623682 +0000
@@ -83,7 +83,9 @@
       }
     }
     elseif ($address instanceof AccountInterface) {
-      return new static($address->getEmail(), $address->getDisplayName(), $address->getPreferredLangcode(), $address);
+      $site_config = \Drupal::config('system.site');
+      $site_mail = $site_config->get('mail') ?: ini_get('sendmail_from');
+      return new static($site_mail, $site_config->get('name'));
     }
     elseif ($address instanceof SymfonyAddress) {
       return new static($address->getAddress(), $address->getName());

Of course this is a bad hack, and i would like to implement a better solution.
I think that at least symfony_mailer should detect when $address->getEmail() is null and avoid the php error.

Other problems have arisen . I gave up and switched to Drupal Symfony Mailer Lite.
Feel free to ignore this.