Reported by Philippe Wittenbergh.
The Example in the last two-thirds of 9.8.3 (Floating a box) is incorrect: a #sibling span is inserted and given the style "clear:right", and the diagram and description describes the 'clear' property as having an effect; yet 'clear' only has an effect on block-level boxes.
I propose fixing this by removing the #sibling span from the example, and instead wrapping the existing loose "End of body contents." in a span and setting that to "display:block; clear:right".
I think this is a better approach than setting "display:block" on the #sibling span; in either case you end up with block-inside-inline, but with the first approach you don't really notice because the inline doesn't resume after the clearing element and so the complexity doesn't really need pointing out in the example, whereas with the second approach you do notice and it probably does need explaining.