Language: PHP
Label: safe
CWE: CWE-79 \u2014 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Code:
    protected function split($string, $config, $context)
    {
        // really, this twiddle should be lazy loaded
        $name = $config->getDefinition('HTML')->doctype->name;
        if ($name == "XHTML 1.1" || $name == "XHTML 2.0") {
            return parent::split($string, $config, $context);
        } else {
            return preg_split('/\s+/', $string);
        }
    }