Function isTimedClipInFlow

packages/core/src/runtime/init.ts:1623–1630

(el: HTMLElement)

  // and avoids disturbing absolute media playback). Computed once per element.
  let timedClipInFlow = new WeakMap<Element, boolean>();
  const isTimedClipInFlow = (el: HTMLElement): boolean => {
    const cached = timedClipInFlow.get(el);
    if (cached !== undefined) return cached;
    const pos = window.getComputedStyle(el).position;
    const inFlow = pos === "static" || pos === "relative" || pos === "sticky";
    timedClipInFlow.set(el, inFlow);
    return inFlow;
  };

  // `display:none` is only safe on a LEAF timed clip (no nested timed clips). On a
  // container it removes the whole subtree, hiding descendants that are still inside