When scrolling further than your current election choices in the sidebar on the election page, the block of choices gets a
position: fixed; added to it... I assume it is meant to be "sticky" and stick to the top of the screen... there is no explicit
bottom applied though so it actually gets stuck ~ 1000px from the top... That means it's invisible if your browser window isn't as tall as that (which is probably most users), otherwise you see this:
It's stuck, half obscured, to the bottom of the screen. It also has no background (it's in a white container when it's static in the sidebar) so it makes a bit of a mess over the footer.
Reproduced on the most recent Chrome, Firefox and Safari on macOS.