I am a complete neophyte at this, but tried pressing F12 to access various debugging tools. I could not find any reference to the comments.
Also interested how you discovered this in the first place?
By the way, when the "what can we do now that we couldn't do in the 90s" debate comes up it always occurs to me that the majority of the applications I use are far more malleable due to being web applications built on its fundamentally open (if admittedly complex and fragile) tool set. So instead of thinking "well, this UI sucks", I can actually fix it myself if I care enough to.
The css for #comments in the inspector pane doesn't specify dimensions for the div, so it should be the size of its child elements. None of the child elements overlap the body text or sidebar, so something else is causing the parent div to cover those elements.
The div directly before #comments is the sidebar, and clicking on it in the inspector pane shows the css floating it.
I then just added a clear: both to #comments using the inspector and it fixed the problem in the main window. You can add css to an element in the inspector in chrome by hitting the "+" in the right-hand pane (there are other ways, but that's probably the easiest).
EDIT: Interesting that I've seen problems like this pop up more than a couple times in recent months. For instance: https://news.ycombinator.com/item?id=7382206
stop with these annoying content protection people!
Although all those extra parameters in the URL are a little odd.
Of course, this particular link doesn't refer to HN in its campaign code, so their statistics are going to get a little confused.
Easiest thing for me was "view source code" and copy from there.