[naugtur]

It's based on HardenedJS.org

The sandbox itself is tight, there's a bug bounty even.

The same technology is behind metamask snaps - plugins in a browser extension.

And Moddable has their own implementation

The biggest problem is endowing too powerful capabilities.

We've got ambitious plans for isolating DOM, but that already failed once before.

[1oooqooq]

so to answer the actual question. if something expects too much browser/dom access to work, it won't?