SVG appears to fail validation

[Paul Millar]

I followed the documentation to generate a test image:

docker run fathyb/html2svg https://google.com/ > google.svg

and fed the resulting file google.svg to the W3C Markup Validation Service. The validator reported a single error:

 Error Line 143, Column 45: SVG element feComposite is missing required attribute in2.

				<feComposite in="flood" operator="atop"/>