QQC2 ComboBox textAt() fails with some models

class Foo {
    Q_GADGET
    Q_PROPERTY(QString bar MEMBER bar CONSTANT)
    QString bar = "Hello";
};

class Bar : public QObject {
    Q_OBJECT
    Q_PROPERTY(QVariantList foos MEMBER foos CONSTANT)

    QVariantList foos{QVariant::fromValue(Foo{}),QVariant::fromValue(Foo{})};
};

ComboBox {
    model: Bar.foos
    textRole: "bar"
    onCurrentIndexChanged: console.log(textAt(currentIndex))
}

ComboBox {
    model: ["Foo", "bar"] // Works fine
    onCurrentIndexChanged: console.log(textAt(currentIndex))
}

ComboBox {
    model: [{bar: "Hello", foo: "Foo"}] // Works fine
    textRole: "bar"
    onCurrentIndexChanged: console.log(textAt(currentIndex))
}