scroll-behavior:smooth confuses scrollIntoView()

In Firefox Nightly 39.0a1 (2015-03-02) the DOM method Element.scrollIntoView() scrolls to different positions depending on the scroll container and body having scroll-behavior:smooth set or not.

Note: Varying target position seems to depend on the position the element had before scrolling. Try scrolling the container to some other position, go back to top, hit a button. E.g. hit scrollIntoView(true) with smooth enabled two times to experience this. First you'll see the container scrolled out of view. Second you'll see the container properly aligned to top


scroll-behavior:smooth on container and body


scroll-behavior:smooth on container and scroll-behavior:auto on body


scroll-behavior:auto on container and body


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