[css-sizing] Should last remembered size be removed if the element is removed from the document?

https://drafts.csswg.org/css-sizing-4/#last-remembered

At the time that ResizeObserver events are determined and delivered, if an element has a last remembered size but does not have contain-intrinsic-size: auto, remove its last remembered size.

Note: The last remembered size is state attached to the element, not any particular box generated by the element. So long as the element retains contain-intrinsic-size: auto, it will remember its last remembered size even across changes such as going to/from display: none.

Should the last remembered size survive the removal of the element from the document?

If not, should this be checked "at the time that ResizeObserver events are determined and delivered"? Or should it be removed immediately?

Start with the linked CSS Sizing Level 4 “last remembered” definition and the Resize Observer specification, then compare the quoted removal rule with the element-removal case. Determine whether the size should survive removal and when removal should occur; the issue is done when the specification behavior and corresponding wording are resolved.