@Override
  public void observeNewIsPostMergeState(final MergeStateHandler mergeStateHandler) {
    newMergeStateCallbackSubscribers.subscribe(mergeStateHandler);
  }
Instantiates a new Post merge context.

@param difficulty the difficulty
consensus/merge/src/main/java/org/hyperledger/besu/consensus/merge/PostMergeContext.java