https://developer.mozilla.org/en-US/docs/Web/API/SVGFEGaussianBlurElement/stdDeviationX
SVGFEGaussianBlurElement: stdDeviationX property - Web APIs | MDN
The stdDeviationX read-only property of the SVGFEGaussianBlurElement interface reflects the (possibly automatically computed) X component of the stdDeviation...
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