Fixed html element use (or abuse depending on one's prerogative) for the page background is the cause. Disabling them on the page with user css fixes it. I thin

Fixed html element use (or abuse depending on one's prerogative) for the page background is the cause. Disabling them on the page with user css fixes it. I think they're mostly an anti-pattern and poor UX, but a lot of designers and developers love to use them these days, unfortunately. Using this http://pastie.org/7942978 http://pastie.org/7942978 with user css will disable them for you on any sites you encouter.