code: private void addOtherMasterLogs(Container result) {
          final Jenkins jenkins = Jenkins.getInstance();
          File[] files = jenkins.getRootDir().listFiles(ROTATED_LOGFILE_FILTER);
          if (files != null) {
              for (File f : files) {
                  result.add(new FileContent("other-logs/{0}", new String[]{f.getName()}, f));
              }
          }
          File logs = getLogsRoot();
          files = logs.listFiles(ROTATED_LOGFILE_FILTER);
          if (files != null) {
              for (File f : files) {
                  result.add(new FileContent("other-logs/{0}", new String[]{f.getName()}, f));
              }
          }
  
          File taskLogs = new File(logs, "tasks");
          files = taskLogs.listFiles(ROTATED_LOGFILE_FILTER);
          if (files != null) {
              for (File f : files) {
                  result.add(new FileContent("other-logs/{0}", new String[]{f.getName()}, f));
              }
          }
      }
docs: Grabs any files that look like log files directly under {@code $JENKINS_HOME}, just in case
  any of them are useful.
  Does not add anything if Jenkins instance is unavailable.
  Some plugins write log files here.