I've encountered a difference in behavior, which I think might be a bug.

Here's how I have my ListBox defined:

<ListBox
  Style=SettingListBoxStyle
  VirtualizingStackPanel.IsVirtualizing=False
  VirtualizingPanel.CacheLength=10 />

<Style x:Key=SettingListBoxStyle>
  <Setter Property=Template>
    <Setter.Value>
      <ControlTemplate>
        <ScrollViewer CanContentScroll=False>
          <ItemsPresenter Margin=15,10,0,185

Here's the behavior I'm seeing:

• With it defined as listed above:
  • Using the mouse, I can click-drag to scroll down, and end up with 185 pixels of blank space at the bottom of the list box.
    • This is what I want. We have other things on the screen, and we want the list box contents to not be underneath them.
  • Using the keyboard, I can move down to the last item in the list, but it's all the way at the bottom of the screen. There's no gap of 185 pixels of blank space.
    • This is not what I want.
• If I switch it to IsVirtualizing=True and CanContentScroll=True:
  • Using the mouse, I can click-drag to end up with 185 pixels of blank space at the bottom of the list box.
  • Using the keyboard, I can move down to the list item on the list. As I scroll down, the focused item is always kept 185 pixels from the bottom, and when I reach the last item, there is 185 pixels of blank space.
    • Both of these is what I want.

I'm wondering if this is a bug. It's obviously aware of the focused item so it can scroll it to be on the screen, but it should be taking the 185 pixel margin into account and scrolling a bit further.