New Fixed position bug on iOS8

Question

I have a site with a fixed header and slide-out sidebars. With iOS7 in portrait orientation, the fixed header stays fixed when the sidebar is visible, but on iOS8 the header

Answer 1

A little late to the party, but adding

html, body {
    overflow-x: hidden;
    overflow-y: scroll;
}

Will fix the offset scrolling on fixed elements that are offset (eg. left:20px) in iOS 8.