Since base64 image urls are just that - urls - it should work. That said, you wouldn't want a sprite in there (unless used as a custom property). You'd just want individual images. That said, reusability, readability, and effort to change the icons later can make this more tedious than it's worth for pagespeed.
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Since base64 image urls are just that - urls - it should work. That said, you wouldn't want a sprite in there (unless used as a custom property). You'd just want individual images. That said, reusability, readability, and effort to change the icons later can make this more tedious than it's worth for pagespeed.