As with every tool like this that I have tried, it can't handle large, realistic JSONs coming down from websites. It died with a 1.5 mb JSON, I just tried, anyway.
This is why I use JQ, which I have seen tackle gigabyte-size files.
I've done my best to optimize it, although there's still room for improvement, but it's quite challenging (but I'll give it a try). The reason is that we're constrained by the browser's UI thread being single-threaded, so almost all online JSON tools will lag or freeze when handling large amounts of data (e.g., over 1MB).
This is why I use JQ, which I have seen tackle gigabyte-size files.