code: public boolean equalsIgnoreCase(final StrBuilder other) {
          if (this == other) {
              return true;
          }
          if (this.size != other.size) {
              return false;
          }
          final char thisBuf[] = this.buffer;
          final char otherBuf[] = other.buffer;
          for (int i = size - 1; i >= 0; i--) {
              final char c1 = thisBuf[i];
              final char c2 = otherBuf[i];
              if (c1 != c2 && Character.toUpperCase(c1) != Character.toUpperCase(c2)) {
                  return false;
              }
          }
          return true;
      }
docs: Checks the contents of this builder against another to see if they
  contain the same character content ignoring case.
  
  @param other  the object to check, null returns false
  @return true if the builders contain the same characters in the same order