);\n  range.setStart(start, 0);\n  range.setEnd(end, 0);\n  const { commonAncestorContainer } = range;\n\n  // Both nodes are inside #document\n  if (\n    (element1 !== commonAncestorContainer &&\n      element2 !== commonAncestorContainer) ||\n    start.contains(end)\n  ) {\n    if (isOffsetContainer(commonAncestorContainer)) {\n      return commonAncestorContainer;\n    }\n\n    return getOffsetParent(commonAncestorContainer);\n  }\n\n  // one of the nodes is inside shadowDOM, find which one\n...