Rails 5 ActionController::InvalidAuthenticityToken error

As indicated in Devise documentation notes for Rails 5

For Rails 5, note that protect_from_forgery is no longer prepended
to the before_action chain, so if you have set authenticate_user
before protect_from_forgery, your request will result in “Can’t
verify CSRF token authenticity.” To resolve this, either change the
order in which you call them, or use protect_from_forgery prepend:
true.