Firefox ES6, get class constructor name

Question

I have problems getting the name of the constructor when using ES6 classes in Firefox. In Chromium it works fine, but Firefox seem to have some kind of bug? In Firefox I only get an empty string back. Anyone that knows of a workaround?

class MyClass {}
let a = new MyClass();
console.log(a.constructor.name);

Answer 1

I think it is a bug (according to the comment below).

It appears that specifying an explicit constructor exhibits the correct behavior in Firefox (even the latest version 48).

class MyClassWithConstructor {
  constructor() {
    console.log("Explicit Constructor")
  }
}

class MyClassWithoutConstructor {}

$('#with').click(function() {
	let tmp = new MyClassWithConstructor();
	alert("MyClassWithConstructor name = " + tmp.constructor.name);
})

$('#without').click(function() {
	let tmp = new MyClassWithoutConstructor();
	alert("MyClassWithConstructor name = " + tmp.constructor.name);
})

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id=with>With Constructor</button>

<button id=without>Without Constructor</button>

Here's a link to JSFiddle: https://jsfiddle.net/jc7g5crp/