• While auditing the code we found the below error code was generated in the system log :
  

PHP Fatal error: Uncaught TypeError: Argument 1 passed to MagentoEmailModelTemplate::setVars() must be of the type array, null given

Above Error throwing due to adding comma separated email in Sales Emails > Order > order copy

check the below screenshot for reference:

• Please follow the below steps to get resolved error:   –

  It has the issue with the file which has below path

vendor/magento/module-sales/Model/Order/Email/SenderBuilder.php

Please override the above file by

Replacing this Function :

public function sendCopyTo()
    {
        $copyTo = $this->identityContainer->getEmailCopyTo();

        if (!empty($copyTo) && $this->identityContainer->getCopyMethod() == 'copy') {
            $this->configureEmailTemplate();
            foreach ($copyTo as $email) {
                $this->transportBuilder->addTo($email);
                $transport = $this->transportBuilder->getTransport();
                $transport->sendMessage();
            }
        }
    }

With :

public function sendCopyTo()
    {
        $copyTo = $this->identityContainer->getEmailCopyTo();

        if (!empty($copyTo) && $this->identityContainer->getCopyMethod() == 'copy') {
            
            foreach ($copyTo as $email) {
                $this->configureEmailTemplate();
                $this->transportBuilder->addTo($email);
                $transport = $this->transportBuilder->getTransport();
                $transport->sendMessage();
            }
        }
    }

That’s It! Now you can add multiple emails with comma-separated.

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