Sender Header Must Be instance of Symfony\Component\Mime\Header\MailboxHeader, got Symfony\Component\Mime\Header\MailboxListHeader

[gusdemayo]

Patched with

--- a/vendor/magepal/magento2-gmailsmtpapp/Mail/Smtp.php
+++ b/vendor/magepal/magento2-gmailsmtpapp/Mail/Smtp.php	(date 1753892947344)
@@ -152,13 +152,13 @@

         if ($setFromEmail !== null && $dataHelper->getConfigSetFrom()) {
             if ($setFromEmail instanceof Address) {
-                $message->getHeaders()->addMailboxListHeader('Sender', [$setFromEmail]);
+                $message->getHeaders()->addMailboxHeader('Sender', $setFromEmail);
             } elseif (!empty($setFromEmail)) {
                 $name = $messageFromAddress instanceof Address ? $messageFromAddress->getName() : $setFromEmail;

-                $message->getHeaders()->addMailboxListHeader(
+                $message->getHeaders()->addMailboxHeader(
                     'Sender',
-                    [new Address($setFromEmail, $name)]
+                    new Address($setFromEmail, $name)
                 );
             }
         }

[JustinElst]

legit