docs: private Multimap<String, I_CmsFormField> getFieldsByGroup(Collection<I_CmsFormField> fields) {
  
          Multimap<String, I_CmsFormField> result = ArrayListMultimap.create();
          for (I_CmsFormField field : fields) {
              String group = field.getLayoutData().get(LD_GROUP);
              result.put(group, field);
          }
          return result;
      }