I'm assuming that this is an anti-aliasing effect on rendering the font. SVG is rendering these fonts and not HTML.
SVG has a property called 'text-rendering' that I tried with all the styles: optimize-speed, optimize-legibility, geometric-precision, default. None of these seemed to make any difference at all.
Created attachment 733812 [details] Text-rendering: geometric-precision
Created attachment 742013 [details] Fuzzy Text
Created attachment 742014 [details] SVG clean text
The culprit was an svg property: stroke. This is now fixed in: master commit: c430d28.