User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:23.0) Gecko/20100101 Firefox/23.0 (Beta/Release) Build ID: 20130814063812 Steps to reproduce: I made an example on jsfiddle, so you can see the bug yourself: http://jsfiddle.net/Joshua82/LxsgC/ This problem only occurs in Firefox for Android. Every other browser works fine. The example contains three divs - a blue header, green footer and content div between both. In the content section there are some canvas each with a black rectangle. Actual results: When scrolling the content div the rectangles go over the header and footer divs. Expected results: The rectangle should vanish with the canvas containing it at the border of content div.

I can reproduce this on mobile using your test-case and wasn't able to reproduce on desktop. I suspect this to be a core issue.

Likely the same issue as bug 866585.

This is fixed via bug 854873.