Confirmed Xara Pro+ v21.2 has the same Parser but v18.0 fails with:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
XML Parsing error - line2, pos 11:
DTD is prohibited.
<!--Generator: Xara Designer (www.xara.com), SVG filter version: 6.6.0.1-->

@Xara - get Magix to fix this in the next 9 days or my Update Service will have expired and I'll be stuck with a buggy v18.0! [Sorry - my sarcasm filter is also buggy]

Acorn