I totally understand. It’s not recommended to modify the source code but I understand it for dire circumstances.
There plugin’s tracking code is minified which makes it somewhat hard to read. Luckily because I helped write the code, I know exactly what you should edit to start collecting hidden input fields.
The file you’d want to edit is plugins/leadin/assets/js/build/leadin-tracking.min.js. All you need to do is remove the piece of jQuery in bold below that skips hidden elements:
$this.find(‘input[type!=”submit”], textarea’).not(‘input[type=”hidden”], input[type=”radio”], input[type=”password”]’).each(function(){…});
Becomes…
$this.find(‘input[type!=”submit”], textarea’).not(‘input[type=”radio”], input[type=”password”]’).each(function(){…});
Whenever you update the plugin you’ll need to keep making this change. Sorry I don’t have a permanent fix for you. One of the reasons Leadin is so easy to use is because we make opinionated decisions that cover the majority of use cases about how the plugin should operate to cut down on decisions for our users instead of adding a setting for every thing. Hope you understand.