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%r{
        (?:
              ^[ ]{0,#{TabWidth - 1}}              # Indent < tab width
              (#{ListMarkerAny})                   # unordered or ordered ($1)
              [ ]+                                         # At least one space
        )
        (?m:.+?)                                            # item content (include newlines)
        (?:
                \z                                         # Either EOF
              |                                                    #  or
                \n{2,}                                     # Blank line...
                (?=\S)                                     # ...followed by non-space
                (?![ ]*                                    # ...but not another item
                      (#{ListMarkerAny})
                 [ ]+)
        )
}x