Bugzilla

So: Here's the specification argument for why Firefox is in the wrong here: 

We're evaluating a `new` expression, and so we end up in [13.3.5.1.1 EvaluateNew](https://tc39.es/ecma262/#sec-evaluatenew). Step 6 is Construct, which in turn calls into [10.2.2 [[Construct]]](https://tc39.es/ecma262/#sec-construct). 

In this case, we take step 6, and initializes instance elements before evaluating the constructor in step 8. 

So this should work. I'll dig though to see why we don't do it in this order tomorrow.

So: Here's the specification argument for why Firefox is in the wrong here: 

We're evaluating a `new` expression, and so we end up in [13.3.5.1.1 EvaluateNew](https://tc39.es/ecma262/#sec-evaluatenew). Step 6 is Construct, which in turn calls into [10.2.2 [[Construct]]](https://tc39.es/ecma262/#sec-ecmascript-function-objects-construct-argumentslist-newtarget). 

In this case, we take step 6, and initializes instance elements before evaluating the constructor in step 8. 

So this should work. I'll dig though to see why we don't do it in this order tomorrow.