Alt+Left shortcut doesn't work on MenuItem

import Qt.labs.platform 1.1 as Labs
import QtQuick.Controls 2.15
import QtQuick 2.15

ApplicationWindow {
    width: 400
    height: 300

    Labs.MenuBar {
        Labs.Menu {
            title: "&Control"

            Labs.MenuItem {
                text: "Back"
                shortcut: "Alt+Left"
                onTriggered: console.log("back")
            }
        }
    }
}