Magento 2.3.3 order confirmation as att00001.htm

[Nicolaikimbrer]

Hi Guys

After upgrading to 2.3.3 

I now get the Order confirmation as an attached file att00001.htm

and the email is blank ?

Whats wrong? I have never seen this before

[markus_tunger]

I have the same issue.

[samoudi2006 · Accepted solution]

Fix:  vendor/zendframework/zend-mail/src/Headers.php in line 514

         $current = $headers;
-        $current->setEncoding($encoding);
+        // PATCH
+        //$current->setEncoding($encoding);
+        $current->setEncoding($key === 'contentdisposition' && $current->getFieldValue(false) === 'inline' ? 'ASCII' : $encoding);
+        // ~PATCH
         $this->headers[$index] = $current;
         return $current;

[martijnvan5c52]

I know this is old, but could you please elaborate as to why this works? And, for that matter, why would any e-mail client interpret an e-mail with a UTF-8 encoded header as an attachment?

Thank you kindly in advanced!