Graphics Render Error if conbine QQuickWidget with QWindow(GL rendering) on Intel integrated GPU

Repoducable environment:

• Windows 10.
• Qt 5.15.7 msvc 2019 64bit or Qt 5.15.2 msvc 2019 64bit
• Intel UHD Graphics 620 / 630.
  • Driver data: 2017/1/18 Driver version: 21.20.16.4590 Good, no error.
  • Driver data: 2019/9/25 Driver version: 26.20.100.7263 Bad.
  • Driver data: 2019/6/27 Driver version: 26.20.100.7000 Bad.

Create a QQuickWidget and a QWindow, the QWindow is wrapped as a QWidget, using QWidget::createWindowContainer API. Put the QQuickWidget and QWindow into one layout and set the layout to QMainwindow.

Use raw OpenGL APIs render to the QWindow results graphic error

This only repoducable on integrated Intel GPU with latest version of driver. I have tried a old one(2017 version) and it works fine.

Attached is a example, there is a pushbutton in the bottom of the mainwindow. Click it will arouse a GLpaint of "green" color.

Using NVidia GPU, the result is Ok, while using Intel GPU activated, it looks like the background pic was zoomed in.