Not really. I've written a bunch of code to try maintain the limited support for it that already exists in GodotJS, but I've never really tried it. Main reason I haven't is I'm dependent on Web Worker(-like) APIs in GodotJS, and they're currently missing for JavaScript Core. But since I actually wrote some of those APIs, that's not really an excuse, I can port them easily enough.

So, yeah, I should really give it a shot. Thanks for the reminder.