I don’t know. What it looks like on my end is that scrolling takes time. It is as though my browser has to do some shit to figure out what the text is, instead of just displaying it like on a normal page.
So I read a line, hit down arrow, nothing happens, I start reading the next line etc. After a while the page starts jumping around like it’s doing all the down arrows at irregular intervals. Ok, that’s annoying, so I stop hitting down arrow and instead read the 1-2 paragraphs that are on the top of the screen, then hit page down. Nothing happens, hit page down again etc. So I scroll back up to where I was, hitting page up once at a time and waiting for the page to scroll like it’s twenty years ago and I just downloaded a large picture. Then I read the part of the text that I can see, hit page down again, sit and wait until it reacts, notice that I don’t understand what I’m reading, notice that that’s because I skipped a paragraph because it was behind the hoverboard, hit page up to find where I was and then try to scroll down part of a screen using the scrollbar. Nothing happens. I wait a while. The text starts to jump around again, because getting no feedback I scrolled a long way. Then I gave up.
I don’t remember what the article was about, I didn’t actually get to the meat of it. On most sites I would have given up and forgotten it ever existed after the first time that page down didn’t work instantly.
Firefox 55.0.2 32 bit, on Linux Mint KDE. No relevant add ons (adblock thing, EFF badger thing, greasemonkey but not with any scripts that should load for this page, pop up blocker thing).