Description
Are you submitting a bug report or a feature request?
Bug
What is the current behavior?
Using FieldArrays results in Uncaught TypeError: original.mergeDeepWith is not a function
What is the expected behavior?
Expected to not do that.
Sandbox Link
What's your environment?
redux-form@7.0.4
immutable@4.0.0-rc.7
node@7.10.1
Other information
The method mergeDeepWith has been removed from the List API since 4.0.0-rc.5 so now any interaction with FieldArrays causes this exception to show up.