Debugging Karma, mocha & webpack inside IntelliJ

Question

I am failing to debug mocha unit tests, using karma and webpack. I have the Karma plugin installed, and the chrome extension. But when I'm debugging the IDE would just ignore any breakpoints.

Example of a unit test:

var assert = require('chai').assert;

describe('Test', function () {
    it('always true', function () {
        assert.equal(1 === 1, true);
    });
});