1. Scroll to the bottom of the list on the right.
2. Click to expand the final item in the list.
3. There is no visual cue that you can now scroll down further to see the expansion. The first item in the list that I click on was the final list item, and I thought that nothing had happened (Note: This could just be an issue with OSX's hidden scrollbars. I can't see if you've disabled it on all platforms, but lots of devs are on OSX).
{edit} I guess I should mention my suggestion. If you're already scrolled to the bottom of the scroll area, and then you take an action that expands the scroll area further down, your position in the scroll area should move to the "new" bottom. There are obviously caveats to this though (e.g. if scrolling to the new bottom would scroll your old position off-screen, this may be disorienting to the user depending on the content and other visual cues). {/edit}
Bug Report #2:
I tried to click the "mail@whoishiring.it" at the bottom (as it's a clickable link), and was taken to a CloudFlare page about how it's hiding the email address for "protection." The issue here is that the link text itself is the email address, so nothing is really hidden (except maybe from poorly written bots crawling the web).
NOTE: This is not meant to be negative or down on your work. It's really great, I just like to take the time for some constructive criticism when there the authors' attention is on the threads (and it's not a e.g. Github project -- that I can see -- so I can't really just open an issue in the bug tracker).