Why does the 'addmore' array button prevent propagation?

[adam-clarey]

On line 1305 of jsonform.js there is the line

evt.stopPropagation();

Which means I'm unable to listen for then someone clicks it. I need this event as I have JS to execute when a new array item is added.

I'm guessing there is a reason for this, I just can't see what or how to get around it. For the time being I've commented out this line but that's not a long-term fix.

Ideally there would be an event/hook that gets called whenever a new item is added for just such a need