Yes that is correct. It opens correctly in Designer and Chrome but I cannot find an option to save it as path without <rect> tags as they do not seem to be supported by a lot of other apps.
I already tried the "convert to curves" thing in my toolbar with the arrow right icon.
If it would be just one app failing I would clearly not write here but write to the author of that app. But none of them are working.
If i save the file as .gif and convert it with an online tool to .svg it works.
I get this:
<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 20010904//EN"
"http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
<svg version="1.0" xmlns="http://www.w3.org/2000/svg"
width="590.000000pt" height="590.000000pt" viewBox="0 0 590.000000 590.000000"
preserveAspectRatio="xMidYMid meet">
<g transform="translate(0.000000,590.000000) scale(0.100000,-0.100000)"
fill="#000000" stroke="none">
<path d="M10 5000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M2010 5000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M4010 5000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M10 3000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M2010 3000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M4010 3000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M3900 1000 l0 -1000 1000 0 1000 0 0 1000 0 1000 -1000 0 -1000 0 0
-1000z m1890 0 l0 -890 -890 0 -890 0 0 890 0 890 890 0 890 0 0 -890z"/>
<path d="M10 1000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
<path d="M2010 1000 l0 -890 890 0 890 0 0 890 0 890 -890 0 -890 0 0 -890z"/>
</g>
</svg>
But Affinity Photo creates this:
<?xml version="1.0" encoding="UTF-8" standalone="no"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg width="100%" height="100%" viewBox="0 0 600 600" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xml:space="preserve" xmlns:serif="http://www.serif.com/" style="fill-rule:evenodd;clip-rule:evenodd;stroke-linejoin:round;stroke-miterlimit:2;"><rect x="0" y="0" width="600" height="600" style="fill:#fff;"/><path d="M600,-0l-600,-0l0,600l600,0l0,-600Zm-590.015,9.948l0.621,579.45l579.648,0.82l1.286,-581.755l-581.555,1.485Z"/><rect x="0" y="0" width="200" height="200"/><path d="M200,0l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="200" y="0" width="200" height="200"/><path d="M400,0l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="400" y="0" width="200" height="200"/><path d="M600,0l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="0" y="200" width="200" height="200"/><path d="M200,200l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="200" y="200" width="200" height="200"/><path d="M400,200l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="400" y="200" width="200" height="200"/><path d="M600,200l-200,0l0,200l200,-0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="0" y="400" width="200" height="200"/><path d="M200,400l-200,0l0,200l200,0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="200" y="400" width="200" height="200"/><path d="M400,400l-200,0l0,200l200,0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z" style="fill:#fff;"/><rect x="400" y="400" width="200" height="200" style="fill:#fff;"/><path d="M600,400l-200,0l0,200l200,0l0,-200Zm-189.456,10.544l-0,178.912l178.912,0l0,-178.912l-178.912,-0Z"/></svg>
Which is not competible with any of the font editors I tried (six, all of them gave me errors). Why is there no option to save it as .svg 1.0? Or did I miss it? Is there another problem?