InDesign CC 2019 (14.0.2) on macOS Extendscript bug

Where do we report bugs? Code below works fine on Windows and CC 2018 on Mac. But CC 2019 Mac it hangs the app once clicking the OK button in window 2. I've tried three different Macs including Mojave and High Sierra. All the same result. Pretty sure it's not just me. This bug has broken a number of my scripts that present a secondary window for saving settings.

var w1 = new Window("dialog", "Window 1");
var btnOpenWindow2 = w1.add("button", undefined, "Open Window 2");
var btnOk1 = w1.add("button", undefined, "OK");
btnOpenWindow2.onClick = function () {
    openWindow2();
};
btnOk1 = function () {
    w1.close();
};
w1.show();
function openWindow2 () {
    var w2 = new Window("dialog", "Window 2");
    var btnOk2 = w2.add("button", undefined, "OK");
    btnOk2.onClick = function () {
        w2.close();
    };
    w2.show();
}