Hi. I was able to reproduce the effect described by @amirzabidi. On my desktop, when opening the member’s site from the above link, the “Older Posts” link sometimes sticks momentarily near the top edge of the middle featured image (of three) in the top row of posts on the homepage.
That is caused by how this particular theme loads, first loading the page itself, and then adding in the posts in the grid layout. There’s no way to prevent that (aside perhaps from enabling infinite scroll), but it should also only be noticeable on slower connections, or on a first visit to the page before it gets cached in the browser.