I wish there was an option for off the main thread ("async") parsing of JSON. It's easy to cause UI lag by parsing (or serializing) large objects, and this seems very unnecessary.
I see this sentiment echoed a few times in this discussion thread. I use JSON daily, parsing and serializing everywhere, and yet I've never been in a scenario where I needed to parse a very large JSON object on the client side. The biggest JSON objects I work with are in the neighborhood of ~80 MB, but the client's browser never sees those behemoths. At most I return a few KB to the client's browser via an API response where it is then parsed and consumed.
Is this notably a problem where the back-end is written in JavaScript?
It's a frontend problem, not a backend problem. The case I've seen it most is trying to store large objects in localstorage for consumption offline. You obviously end up with more data in this case.
Mobile browsers are the biggest problem, they (and desktop ie sometimes) can struggle with objects of even a few hundred kb.
