Function timelineMessage

packages/player/src/hyperframes-player.test.ts:1828–1838

(durationInFrames = 120)

  }

  function timelineMessage(durationInFrames = 120) {
    return new MessageEvent("message", {
      source: frameWindow,
      data: {
        source: "hf-preview",
        type: "timeline",
        durationInFrames,
        scenes: [],
      },
    });
  }

  function findControlCalls(action: string) {
    return postSpy.mock.calls.filter((call) => {