Remove duplicate headers

Pick an Excel file (.xlsx, .xlsm, .xlsb, .xls or .ods), say where the table starts (in case there’s a title or loose rows above it) and which columns to use to identify a row as a duplicate. Mainly meant for column headers that repeat in the middle of the data (common in reports built by pasting several tables together), but it also works for any other duplicate row. The first occurrence of each is kept; everything above the table is left untouched.