@ApiStatus.Internal
  public static boolean isHeaderElementType(@NotNull org.intellij.markdown.IElementType markdownType) {
    return markdownType == MarkdownElementTypes.ATX_1 ||
           markdownType == MarkdownElementTypes.ATX_2 ||
           markdownType == MarkdownElementTypes.ATX_3 ||
           markdownType == MarkdownElementTypes.ATX_4 ||
           markdownType == MarkdownElementTypes.ATX_5 ||
           markdownType == MarkdownElementTypes.ATX_6 ||
           markdownType == MarkdownElementTypes.SETEXT_1 ||
           markdownType == MarkdownElementTypes.SETEXT_2;
  }
@ApiStatus.Internal
  public static boolean isHeaderElementType(@NotNull org.intellij.markdown.IElementType markdownType)