} else if (u8a[i] >= 0xF1 && u8a[i] <= 0xF3) /* F1..F3 80..BF 80..BF 80..BF */ {
      if (i + 3 < len) /* Expect a 2nd, 3rd 3th byte */ {
        if (u8a[i + 1] < 0x80 || u8a[i + 1] > 0xBF) {
          // *message = "After a first byte of F1, F2, or F3, expecting a 2nd byte between 80 and BF.";
          // *faulty_bytes = 2;