Cannot call a class as a function

[tlenex]

When i try to extend ES6 class (transpiled to ES5 with babel) as a parent class and I call MyJSFaceCLass.$super.call(this);

I get an error with pointing line to $super.call as mentioned above

Cannot call a class as a function

Was anyone able to migrate from jsface to ES6 successfully? As far as I can tell, I'll need to fork jsface to use new to construct parent object and then extend it, or find a non-standard babel transpiler for transforming classes into pure functions without checking new keyword generated object instance.

Btw. Is this project dead?