Thanks for this code. We'll look over it carefully to see if there are some tricks that we've missed.

But we've tried many libraries, and many approaches, to monitoring and debugging javascript. The browser is a much more hostile, varied and foggy environment than (say) Python. It's much harder to notice when something goes wrong, which browsers and which pages it's common to, narrow it down to the right subset of circumstances and contexts, and then effect a fix.

You can try sending an email every time you catch a window.onerror, but most of what you receive will be irrelevant or inscrutable.

If Proxino can make more sense of things, they could make a huge difference to rich-front-end development.

[I don't know them, I've not yet checked out their product, I'm just trying to persuade you all that they're trying to solve a meaningful (at least to me) problem]