Favorite heart
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The heart a listing or a brand is favourited with. The server passes in what it favourites and the real state, and the heart saves through the favourite action itself; it queues rapid clicks, keeps the count in step optimistically, and animates the like: the fill tints in, the heart spring-pops, and eight dots spray out. Unliking only lets the fill go. Already-liked hearts never pop on mount.
Sizes and counts
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On a photo
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