QQuickWidget scaling issue during switching multi screens when using 2D renderer

Reproducer is attached.

The report from the customer:

When using the Qt Quick 2D Renderer, a window in our application fails to scale properly if the primary monitor is changed while the application is running. This window is an NSPanel, and a QQuickWidget is embedded using winId(). Please review the floatingwindow.mm file included in the attached project.

To reproduce the issue:

1. Open and Run the attached project on a MacBook Pro without connecting an external monitor. 

2. Click on the button to open another window.

(See attached Screenshot 2024-02-06 at 12.52.42.png)

Now, close the lid of the MacBook and allow it to enter sleep mode.

3. Connect an external monitor in clamshell mode using an external keyboard and mouse.

4. The bug will become apparent. You will see the incorrect scaling of blue window.

(See attached Screenshot 2024-02-06 at 12.54.33.png)

Please provide any patch that can be implemented in Qt 5.15.

Note: We reported this bug approximately 5 years ago, but it was marked as "won't do" because QMacNativeWidget has been deprecated. However, the alternative method exhibits the same bug as well. See here https://bugreports.qt.io/browse/QTBUG-76192

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This issue was reproduced at Qt Tokyo office with MacBook Pro (6-Core Intel Core i7, Sonoma 14.0) and a Full-HD display.