How the page --yotube.com/channels-- load their links?

I'm trying to get the subscribed channels list on youtube.com/anyuser/channels. Using python, it is possible to get just some of them (apparently the API return 6 by default). When you open the page, YouTube load the first 10 and more 10 every time you scroll down.I just want to understand how does it work: YouTube save these channels links in another page, and pull them every time you scroll? Since YouTube considers this public information, is there a way to get all the channel, or force YouTube to load them ?