This is also in Radar as 3109180 This is a bit contrived but it happens. Go to a pagethat takes some time to load (http://bluesnews.com/) is what I used When the load is finished, scroll down. Then go to a new page page. Then press the back button and while the old page is still loading, scroll around a bit. When the page load finishes, it jumps to the last saved location even though I've scroll around a bit. It should cancel the scroll on page done if I do any scrolling before the page is finished loading. --- comment added later --- I think this is caused by the onfocus handler on the "search" box which is near the top of the page. --- comment added later --- This happens to me often on many different pages. It's much more noticeable if your internet connection is slow (dialup, flaky Airport).
I was thinking of adding a trap door that would be set when the user first interacts with a page after loading starts, which would prevent any later restoration of the scroll position. This would also be good if they started filling out a form, and we would prevented from scrolling the doc out from under them.
See also discussion in Bug 3390 Comment #16.
*** This bug has been marked as a duplicate of 13770 ***