<li>Unordered list - Item 1</li>
<li>Unordered list - Item 2</li>
<li>Ordered list - Item 1</li>
<li>Ordered list - Item 2</li>
From my reading, when you set
overflow-x computed value is set to
auto which is part of the CSS Spec.
Computed value: as specified, except with visible computing to auto if one of overflow-x or overflow-y is not visible.
This value indicates that the box’s content is clipped to the padding box.
..and since the marker is outside of the
li it's clipped and so hidden.