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Sebastian Markbåge
a5297ece62
Starting a View Transition is an async sequence. Since React can get a sync update in the middle of sequence we sometimes interrupt that sequence. Currently, we don't actually cancel the View Transition so it can just run as a partial. This ensures that we fully skip it when that happens, as well as warn. However, it's very easy to trigger this with just a setState in useLayoutEffect right now. Therefore if we're inside the preparing sequence of a startViewTransition, this delays work that would've normally flushed in a microtask. ~Maybe we want to do the same for Default work already scheduled through a scheduler Task.~ Edit: This was already done. `flushSync` currently will still lead to an interrupted View Transition (with a warning). There's a tradeoff here whether we want to try our best to preserve the guarantees of `flushSync` or favor the animation. It's already possible to suspend at the root with `flushSync` which means it's not always 100% guaranteed to commit anyway. We could treat it as suspended. But let's see how much this is a problem in practice.