Way back when you made a video about your chrome extensions. Great video. Smoothscroll is one of those must have extensions, but they've recently started injecting ads into the webpages you visit. Not cool. What are you using now?
I noticed that too and switched to "Chromium Wheel Smooth Scroller". I had to tone its settings down a bit to fit my taste, but now it's fine for me.
What's sad is that Google allowed the Smoothscroll app to do this. I and many others reported the behavior to them a while ago when it happened, but they let it slide.