Now there are two experimental feature options:

• "New Curves Type": Enables the new data type and a couple of tools that are meant to be in the first release that comes with the new curves object.
• "New Curves Tools": This is only available when the new curve type is available as well. It mainly exists to keep some tools experimental even after the initial curves object is release officially.
  • For now this only includes the curves edit mode which is not usable yet and probably won't be for the initial release.