Scrollbar jumps back to top

When more search results are returned than will fit in the product list pane, the additional products may be viewed by scrolling down with the scrollbar. However, when I scroll down and move my cursor into the list of products (as to select one), the scrollbar jumps back to the top of the display area. Attempts to add products at the bottom of the scrollable area fail. So the products lower down in the list are visible but cannot be clicked/added to the cart.

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