Extra Debugging Helpers not loaded

In options: Debugger -> Locals & Expressions:

If I add a .py file in extra debugging Helpers, then it is not loaded.

It seems like 

addDumperModule (as found in dumpers.py) should call self.setupDumpers() at the end of the function, if it does, everything works fine.

For anyone else hitting this before it is fixed, here is a workaround:
In Debugging Helper Customization add code like this:

theDumper = Dumper()
theDumper.loadDumpers(None)
theDumper.addDumperModule({"path":"C:/.../MyTypes.py"})
theDumper.setupDumpers()

Obviously, fix the path to where your file is.