[johncolanduoni]

I don't think the developers of any of the main browser's JS engines pretend they're not going to be executing hostile code. In fact I struggle to think of better embeddable software sandboxes than V8, SpiderMonkey, etc., especially now that they support WebAssembly.

[movedx]

Good point. These are smart people developing these sandboxes - they know what they're getting themselves, and their users, in for.