Svg text with tspan incorrect rendering

[Nevenit]

Describe the bug
The separate tspan elements within a text field don't get rendered properly.

To Reproduce
Code snippet to reproduce the behavior:

String testImg = '''<svg height="40" width="250" xmlns="http://www.w3.org/2000/svg">
  <text x="5" y="30" fill="red" font-size="35">I Love
    <tspan fill="none" stroke="green">SVG</tspan>!
  </text>
</svg>''';

    pdf.addPage(
      pw.Page(
        build: (pw.Context context) {
          return pw.Center(
            child: pw.SvgImage(svg: testImg)
          );
        },
      ),
    );

Expected behavior
Its a rendering issue visible in the images. The green "SVG" is supposed to be between the red "I Love" and "!" but its after.
Then using tech-anchor="center" should make the whole text element rendered from the center but it seems like all tspan elements act separately? Only tested on MacOS, I would assume the svg renderer would be the same on all platforms?

Screenshots

Flutter Doctor

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! Doctor found issues in 1 category.

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