docs: public static StringBuilder get(FacesContext context, String key, int initialSize) {
          StringBuilder builder = (StringBuilder) context.getAttributes().get(key);
  
          if (builder == null) {
              builder = new StringBuilder(initialSize);
              context.getAttributes().put(key, builder);
          }
          else {
              builder.setLength(0);
          }
  
          return builder;
      }