iframe integration

[razibal]

I'm trying to get bi-directional integration working for nodebb running in an iFrame. One of the last pieces left is ensuring that the post index is captured in the browser session stack. I can get the navigation events captured by listening for 'action:ajaxify.end' and using that to postMessage back to the parent so it can then be used for a pushState. I would also like to capture the post index changes as a user scrolls through the posts so it can be reflected in the parent url. Is there an event I can attach to, so these index changes can be captured?