SVG files with nested svg elements are not considered properly

SVGs with nested svg elements are not handled properly. At the very least from what I can tell, Qt ignores viewBox parameters in the inner svg elements.

Run the test.py script, which opens Computer.svg and saves it as a png file.

You will note that the inner design appears very small, on the top left of the image, instead of displaying the same way as in the SVG, prominently in the center.

Then, edit test.py to use Phrase.svg, which works correctly.

Please let me know if you require more information.

 Tested on PySide 6.0.0 and PySide 6.1.2.