What is the issue with the HTML Standard?

https://drafts.csswg.org/css-contain/#cv-notes has:

Specifically, such changes will take effect between steps 13 and 14 of update the rendering step of the Processing Model (between “run the animation frame callbacks” and “run the update intersection observations steps”).

However run the animation frame callbacks is now step 14, and there's step 15 which takes care of updating style and layout and so on, along with ResizeObserver.

I think this should probably happen either right before that loop in step 15, or inside that loop. But it should happen in the HTML step so it doesn't get out of sync and all these steps are well defined...

Any strong opinions? Maybe once per frame at the beginning of that loop is alright.

cc @vmpstr @noamr @Loirooriol @mrobinson