Your system asks for reduced motion, so VFX-JS draws nothing. Demos on this site show plain HTML.
Type
RunOpts
vfx-js/src/transition/types.ts:130 ↗import type { RunOpts } from "@vfx-js/core";type RunOpts<T extends Transition | TransitionClass = Transition | TransitionClass> = Partial<TransitionSpec<T>>