docs: public static synchronized ThreadBoundOutputStream bindSystemErr() {
          if (null== boundErrPrint) {
              origSystemErr = System.err;
              final ThreadBoundOutputStream newErr = new ThreadBoundOutputStream(origSystemErr);
              boundErrPrint = new ThreadBoundPrintStream(newErr);
              System.setErr(boundErrPrint);
              return newErr;
          } else {
              return boundErrPrint.getThreadBoundOutputStream();
          }
      }