Is there a good way to detect SVG support via Javascript? I'm not fond of this solution, but if we could detect SVG support via Javascript we could change all the images on the page out for SVG versions of them. Having little experience modifying the Mediawiki core though, I'm not sure how feasible this is.
document.implementation.hasFeature("http://www.w3.org/TR/SVG11/feature#BasicStructure", "1.1"),