code/Debug/Model/Core/Email/Template.php
public function decodeSubject($subject)
    {
        if ($this->hasQueue() && $queue = $this->getQueue()) {
            return $queue->getMessageParameters('subject');
        }

        return base64_decode(substr($subject, strlen('=?utf-8?B?'), -1 * strlen('?=')));
    }
public function decodeSubject($subject)
    {
        if ($this->hasQueue() && $queue = $this->getQueue()) {
            return $queue->getMessageParameters('subject');
        }

        return base64_decode(substr($subject, strlen('=?utf-8?B?'), -1 * strlen('?=')));
    }
Returns raw subject

@param $subject
@return string