    private function registerDebuggingScripts () {
        if (YII_DEBUG) {
            Yii::app()->clientScript->registerScript('debuggingErrorHandler',"
            ;(function () {
                if (typeof x2 === 'undefined') return;
                if (x2.DEBUG) {
                    var oldErrorHandler = window.onerror;
                    window.onerror = function (errorMessage, url, lineNumber) {
//                        alert (
//                            'JavaScript Error: ' + url + ': ' + lineNumber + ': ' + errorMessage +
//                            '.\\nTo turn these messages off, set YII_DEBUG to false.');
                        if (oldErrorHandler) return oldErrorHandler (errorMessage, url, lineNumber);
                        return false;
                    };
                }
            }) ();
            ", self::POS_HEAD);
        }
    }
The software 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.