docs: public static void configureProtocolHandler() {
          final String pkgs = System.getProperty("java.protocol.handler.pkgs");
          String newValue = "org.mapfish.print.url";
          if (pkgs != null && !pkgs.contains(newValue)) {
              newValue = newValue + "|" + pkgs;
          } else if (pkgs != null) {
              newValue = pkgs;
          }
          System.setProperty("java.protocol.handler.pkgs", newValue);
      }