The following image from Wikipedia is not rendered properly. The gradient is a square "cut" by something like a mask when displayed in a browser for example. Using Qt, the "cutting" does not happen and the whole square appears over almost all the other elements.

Something close, if not identical to this :

Very few lines of code based on QSvgRenderer and QSvgGenerator, or a QPainter over a QImage saved as a PNG, can show the problem (I don't have such an example ready right now).

I used this version instead, and it is rendered properly.