def generated_pkgdown?
      return false unless extname == '.html'
      return false unless lines.count > 1

      return lines[0].start_with?("<!-- Generated by pkgdown: do not edit by hand -->") ||
             lines[1].start_with?("<!-- Generated by pkgdown: do not edit by hand -->")
    end
def generated_pkgdown?
      return false unless extname == '.html'
      return false unless lines.count > 1

      return lines[0].start_with?("<!-- Generated by pkgdown: do not edit by hand -->") ||
             lines[1].start_with?("<!-- Generated by pkgdown: do not edit by hand -->")
    end
Internal: Is this a pkgdown-generated file?

 A pkgdown-generated file typically contains:
 <!-- Generated by pkgdown: do not edit by hand -->
 on the first or second line.

 Return true or false