code: public boolean shouldDisplay() throws IOException, ServletException {
          if (!Functions.hasPermission(Jenkins.ADMINISTER)) {
              return false;
          }
  
          StaplerRequest req = Stapler.getCurrentRequest();
  
          if (req == null) {
              return false;
          }
          List<Ancestor> ancestors = req.getAncestors();
  
          if (ancestors == null || ancestors.size() == 0) {
              // ???
              return false;
          }
  
          Ancestor a = ancestors.get(ancestors.size() - 1);
          Object o = a.getObject();
  
          // don't show while Jenkins is loading
          if (o instanceof HudsonIsLoading) {
              return false;
          }
          // … or restarting
          if (o instanceof HudsonIsRestarting) {
              return false;
          }
  
          // don't show for some URLs served directly by Jenkins
          if (o instanceof Jenkins) {
              String url = a.getRestOfUrl();
  
              if (ignoredJenkinsRestOfUrls.contains(url)) {
                  return false;
              }
          }
  
          if (getActiveAdministrativeMonitorsCount() == 0) {
              return false;
          }
  
          return true;
      }
docs: Whether the administrative monitors notifier should be shown.
  @return true iff the administrative monitors notifier should be shown.
  @throws IOException
  @throws ServletException