Windows: Image artifacts on blur picker example at fractional scale factors

I was going to translate c++ blur picker effect example (https://doc.qt.io/qt-5/qtwidgets-effects-blurpicker-example.html) to Python and when I have run the code in my PC I have seen lot of artifacts (white flickering rectangles) being drawn during the animation. I don't know what can cause this, but this may be a issue, either from the example or from Qt itself. See the video, please

https://codereview.qt-project.org/c/pyside/pyside-setup/+/379379

Edit: It works fine in Qt 5.15.2, so It should be a Qt6 bug