Well it helps to talk to one of the duktape developers, doesn't it?
I asked about interrupting runaway js, and there is indeed a mechanism.
DUK_USE_EXEC_TIMEOUT_CHECK
https://github.com/svaarala/duktape/blob/master/config/config-options/DUK_USE_EXEC_TIMEOUT_CHECK.yaml
I'll play with this a bit, and perhaps replace our native method detect and stop code with this, since it is more general.
Of course we still have to retain the interrupt code for fetching files from the internet, which is often the slowest part of a long browse.
I've seen one web page pull down 20 js files.
Anyways, if we have any further questions, enhancements, bug reports etc, I have a duktape contact.

Karl Dahlke