unsupported syntax of MEMBER keyword (part of Q_PROPERTY())

The MEMBER keyword is new keyword in Q_PROPERTY macro in Qt 5. The MEMBER keyword is wavy underlined in Qt Creator. It shouldn't be. It is a valid Qt 5 code.

See sample code and attached screenshot.

class MyClass : public QObject
{
    Q_OBJECT
    Q_PROPERTY(QString str MEMBER m_str)

public:
    MyClass(QObject *parent = 0);
    ~MyClass();

signals:

private:
    QString m_str;

};