Enabling redux dev tools causes identity of parts of Immutable state to change when it shouldn't, breaking pure render.

devtools-immutable-bug.js

  let Immutable = require('immutable'), 
      devTools = require('redux-devtools').devTools;
  let { createStore, applyMiddleware, compose } = require('redux');

  let state = Immutable.fromJS({
    one: { number: 1 }
  });

  function reducer(state, action) {
    if(action.type === 'ONE') {
      return state.setIn(['one', 'number'], 11);
    } else {
      return state;
    }
  }

  let store = compose(
    devTools(), // Comment this out and the spec passes
    createStore
  )(reducer, state);

  describe("identity of state.get('one')", () => {
    it("doesn't change when an action is dispatched that doesn't update it", () => {
      // This issue occurs only when the part of the state in question has previously been updated
      store.dispatch({type: 'ONE'});
      // Store a reference to the updated part of the state
      let lastOne = store.getState().get('one');
      // Then call action that updates other parts of the state, or does nothing at all
      store.dispatch({type: 'ANYTHING'});
      // Now compare identity
      // This fails, they have the same attributes but not the same identity
      expect(lastOne === store.getState().get('one')).toBeTruthy();
    });
  });