When I push down the arrow key in my keyboard, Firefox scrolls site to its bottom. How can I configure Firefox to scroll smoothly, so that I can see couple of new lines as I press the key? I have Firefox 25.0 and Ubuntu 13.10. I tried to reinstall Firefox and in preferences I chose smooth auto scrolling. It looks like there is a cursor in the WWW-site I'm watching and by pressing keys the cursor jump between different links.