For simple fills, for anything other than `solid` types, the preview doesn't render anything, and in the console, the arcgis internal "previewSymbol2D.js" throws an error against ".toCss is not a function".
Relevant Codepen, testing on the `/next/` version (also tested against 4.24):
https://codepen.io/Tickthokk/pen/oNdwoEv
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It'd be great to render polygons that are not solid!
Thank you 🙂