$index = $this->storeCaptcha( $info );
$title = Title::makeTitle( NS_SPECIAL, 'Captcha/image' );
$resultArr['captcha']['type'] = 'image';
+ $resultArr['captcha']['mime'] = 'image/png';
$resultArr['captcha']['id'] = $index;
$resultArr['captcha']['url'] = $title->getLocalUrl( 'wpCaptchaId=' . urlencode( $index ) );
}