private Map<TransactionSelector, SelectorState<?, ? extends StateDuplicator<?>>>
      duplicateLastState() {
    return getLast().entrySet().stream()
        .collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue().duplicated()));
  }
Called at the start of block selection, when the initialization is done, to prepare a new
working state based on the initial state.

<p>After this method is called, it is not possible to call anymore {@link
#createSelectorState(TransactionSelector, Object, StateDuplicator)}
plugin-api/src/main/java/org/hyperledger/besu/plugin/services/txselection/SelectorsStateManager.java