Now I'm thinking about performance, and that could be a problem.
duktape is allocating and freeing zillions of things all the time, most of them not objects.
duk_get_string, duk_push_string, etc.
Edbrowse is the same way if you look at the code.
So pass all those pointers across and scan through all tags in all open windows against all pointers? I don't think so.
No - I'd have to maintain a watch list in the js process.
My own wrapper around get_heapptr() that says, this is an important pointer that will be linked to an edbrowse tag, keep it in a list.
Then our wrapper around free could scan through this list and 99% of the time it wouldn't match so do nothing.
If it does match then remove it from the watch list and pass it over to edbrowse as a side effect.

To do it right, it's not easy peasy; might be about the same effort is generated IDs,
but the free interceptor might still win the day, primarily because it allows garbage collection to continue, and web pages will not accumulate objects second by second by second.

Karl Dahlke