I have Infinite Scroll on both my admin and test user accounts and I get the same thing. We have an a large database with more than 4K entries and it is very annoying. It is also very annoying that I can't jump to a specific line number!
Another problem with Infinite Scroll for people using a UHD 3840 x 2160 monitors and Chrome with a a window larger than 1920x1080, Infinite Scroll just stops after 40 or so entries and will not replenish until you make the Chrome window size smaller and refresh the page. It's a really weird bug. Point being, there may be other bugs I have not yet encountered.