Enter on a paragraph with a check box tag gives the new paragraph an
unchecked copy of each check box; Enter on an empty item drops its check
boxes, as Enter on an empty bullet ends a list. OneNote 2010 carries no
tag on Enter and keeps an empty item's tag below a plain paragraph
(corpus/structural-probe); a page edited this way cold-opens in OneNote
2010 with the new items unchecked. Each Enter is one undo step and one
revision.

Assisted-by: claude-opus-5.5