Google is testing infinite or continuous scroll on the desktop search results again. As a reminder, Google launched continuous scroll for mobile search last October. Google has also tested infinite scroll on desktop search for many many many years.
Brodie Clark spotted the latest Google infinite scroll test, and posted about it on Twitter with this GIF/video:
Again, we have seen Google test this countless times, as far back as 2015 and even back to 2011.
I personally cannot replicate this specific test but Google is always testing.
Forum discussion at Twitter.
