I use the following code to create a "MessageDialog"

MessageDialog {
    id: messageDialog
    icon: StandardIcon.Question
    title: "Action?"
    text: "Would you like to perform an action right now?"
    standardButtons: StandardButton.Yes | StandardButton.No
    onYes: {
        console.log("Performing Action")
		this.close()
    }
    onNo: this.close()
}

I have a button which when clicked calls messageDialog.open(). The dialog opens fine the first time but if I open it a second time I get the following output message

void QCocoaWindow::syncWindowState(Qt::WindowState) invalid window content view size, check your window geometry

This only happens in 5.3 RC, I opened the 5.3 beta install and did a clean/qmake/build/run and the problem was gone. Switched back to 5.3 RC and did the clean/qmake/build/run and the problem was back.

I tested this on a MacPro running 10.8.5 and a MacBookPro running 10.9.2. Both had the problem (I tested on iOS and Android and neither had the problem)