This was a problem back in
QTBUG-45559 and seems to have broken again after https://codereview.qt-project.org/c/qt/qtbase/+/324352
The resulting image seems to be wrapped with 3 pixels and some extra rgb pixels in the lower left corner:
- Build attached example.
- Use the windows snipping tool to snip a part of for example the Qt logo.
- Paste in the example app.