A value of 'none' turns off the display of the element, including children elements and the surrounding box. The only value of display that made a difference to the default rendering was none . All P elements started on a new line, with no indent when a list-item was called for. All I elements remained inline, with no list item identifier. The elements with a display of none were not rendered, as expected.
P insists on remaining a block element.
An indent and vertical space are added. I , on the other hand, gave us four different and correct renderings. With block , it moved to a new line, without additional vertical space. It can be used only as a toggle, with the none value, to turn rendering on or off. Navigator has much better support of this CSS property.