message: [bugfix] Collapse: use double raf to ensure animation can start
diff: @@ -74,9 +74,13 @@ export default createComponent({
  if (offsetHeight) {
  const contentHeight = `${offsetHeight}px`;
  wrapper.style.height = expanded ? 0 : contentHeight;
  +
  + // use double raf to ensure animation can start in mobile safari
  + raf(() => {
  raf(() => {
  wrapper.style.height = expanded ? contentHeight : 0;
  });
  + });
  } else {
  this.onTransitionEnd();
  }
  