Here's a quick and efficient way to remove `autoplay` from videos if the user prefers reduced motion https://codepen.io/jaffathecake/pen/vENzMmd?editors=1010

`animationstart` is one of my favourite hacks for monitoring elements appearing in the DOM.

Prevent autoplay if prefers reduced motion

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@jaffathecake does this approach a polyfill for elementtiming? It seems like it might be closer to “paint” than MutationObserver. And more declarative.
@kseudonym I'm not sure about elementtiming, but animation events fire in the render steps, so yeah, close to (but before) paint