code: @Override
      protected List<ExtensionComponent<D>> load() {
          if (jenkins == null) {
              // Should never happen on the real instance
              LOGGER.log(Level.WARNING, "Cannot load extension components, because Jenkins instance has not been assigned yet");
              return Collections.emptyList();
          }
          return _load(getDescriptorExtensionList().getComponents());
      }
docs: Loading the descriptors in this case means filtering the descriptor from the master {@link ExtensionList}.