This is an exploratory issue. wasm-bindgen is making great progress and might be much faster than stdweb for passing data between Rust and js. That might be very interesting, especially for opengl buffers.
https://hacks.mozilla.org/2018/04/javascript-to-rust-and-back-again-a-wasm-bindgen-tale/

Maybe we could start investigating wasm-bindgen on some lower module, like uni_pad or uni_snd