Where is the stream auto-load script?

Hi guys

We are building a new template which will sport a wire-frame you'd expect to find in a modern web applications very similar to Twitch for example.
However, we are going to have 50px tall fixed bar at the bottom of the page which will inevitably mean that we can not scroll the browser page to the very bottom.
Unfortunately, this is needed for event to kick in and fires the auto-load of the stream.

i have question and the suggestion.
First, the question.
Where is the script that "decides" when to fire up an autoload so i can change it per my requirements?

And now suggestion, though it might be too optimistic.
Can this event be fired when page is around 70-80% scrolled down?
This will in many cases initiate loading before user even reach the end of the page providing a better stream browsing experience
Ofcourse this can be potential problem with sites that have modules under component area, but hey, you can provide the backend configuration for it too.