Completely unscientific test: if I load the following website in Firefox 24 (on Windows 8), the page scrolls very sluggishly (as it did in previous Firefox versions). The same page scrolls fine in Chrome. I don't know what is causing the difference. Is it the images? Or something else? For info, Firefox is my main web browser and I have never switched to Chrome (nor do I intend to).

Warning - the website is ridiculously image heavy (it's a gallery of Android app screenshots)

http://androidniceties.tumblr.com/