Setting Material.background color to Transparent causes click animation to fail

Execute the following code, will result in the material design animation to only display EVERY OTHER time the button is clicked.

import QtQuick 2.9
import QtQuick.Controls 2.2
import QtQuick.Controls.Material 2.2 

Button {
     Material.elevation: 1   
     Material.background: "#00000000"  
     width: 200  
     height: 200
}