Just exploring Svelte, stores and contexts with a cliché todo app. Site
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Findings
animate
should be directly used in an each block otherwise you'll get: An element that uses the animate directive must be the immediate child of a keyed each blocksvelte(invalid-animation)
So putting these animations in a Svelte components is impossible at the moment. So you'll have to write your Svelte "component" directly inside your parent component. Or move it to a Svelte component and wrap it with a native dom element inside the each block.