I can't wait until this Browser-on-JS/WASM-on-Canvas loads an IFrame from a site that also has its own Browser-on-JS/WASM-on-Canvas.
Hell, the inner IFrame is probably going to get around IFrame recursion and domain rules too.
We're going to eventually end up with IFrame fork bombs, and IFrame topologies that cannot be meaningfully mapped to Euclidean space (amongst all the other privacy, user control, etc. concerns, of course).