Scrolling hiccups

I am still trying to get accustomed to the new place. I noticed that when in a thread, the scrolling is jumpy to say the least.

I don't know if there are still people working on such issues, but it makes reading very difficult, especially since I have not found a way to jump to the last message read. I am wondering if the issue is not due to the Avatars, but even when they finally show up, it is still jumpy.