Anne van Kesteren

Right and for parts where they would use the same code to implement something that would not count.

We could make it some kind of assert that the value previously returned is not equal to the value returned now.

This isn't web observable I think. We could add a code path to handle it explicitly, but we'd need to be very careful not to run into any issues later.

@syg so what would be the net impact on the web platform? The ability to create synthetic modules through `globalThis.BuiltinModule`? Or is that also host-configurable? (I'm not sure to what...

At least from discussion the intent is that the two APIs operate on the same underlying model, so yes. That should probably be more clearly stated in the specification.

I suspect that would allow for creation of a high-resolution timer and would therefore need to be behind the cross-origin isolated flag (COOP+COEP) at least in some host environments.

Chrome's site isolation is not sufficient mitigation and they also plan to migrate to a more restrictive environment: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer/Planned_changes.

I'm saying that if it's allowed there needs to be a hook for host environments that can indicate whether it's supported so it can plug into the cross-origin isolated flag...

No it's not, it's a host problem and something the host needs to have a say over. I.e., it's a spec problem.

https://tc39.es/ecma262/#sec-overview second sentence.