This test asserts the behavior seemingly agreed upon through https://github.com/w3c/csswg-drafts/issues/11044#issuecomment-2486935794. This is unlikely to be the final specified behavior, hence the test is marked tentative.

New BFC fits next to float, so top margins will collapse, so we want the stretched height to match .outer's height.

New BFC does not fit next to float, so margins DON'T collapse, but for simplicity we still ignore margins when stretch sizing

In-flow child overlaps the float, so margins DO collapse, so we want the stretched height to match .outer's height.

In-flow child clears the float, so margins DON'T collapse, but for simplicity we still ignore margins when stretch sizing