Google’s John Mueller said in a webmaster hangout on YouTube that Google’s probably won’t see your content if it is hidden behind a ‘load more’ button or a scroll event.
“We render the page in a way that we take a very long viewport, like a really long monitor, and we try to load the page. Then we tell the page like ‘this is your viewport, this is tall’ and then we give the page time to load the content that would be visible there.
So essentially, with that setup, if you recognize that this part of the content is visible and you show it, then we’d be able to index that. That’s the more guaranteed way of doing that.
The other ways, where we have to watch out for a scroll event or for someone to click a ‘load more’ button, something like that, that’s usually something that Googlebot tends not to do.
So in particular, we don’t know which which elements to click on to see if something would load. That’s something where probably we would not be able to pick up that content. […]