Valentin Pletzer noticed Google testing having the related search boxes carousel stick to the top of the mobile search results as you scroll. So those related searches just hang out at the top of the search results even if you scroll past them.

Here is a static image Valentin posted on Twitter:

Here are some more from him:

Saad AK posted a video of this in action as well, which makes it easier to see:

I am not a fan.

Forum discussion at Twitter.