Need to pass all the descendant of root to handle button invoker's top most popover ancestor

[cathiechen]

https://html.spec.whatwg.org/multipage/popover.html#topmost-popover-ancestor

For each button invoker that is a descendant of newPopover's root, in tree order:

Here we need to pass all the descendants, it is not very effective for performance.
I tried to maintain a list of button invokers for each popover, but it does not work, especially the spec requires tree order.
Should we optimize this?
Any ideas? @jakearchibald @emilio @nt1m

[jakearchibald]

Related: #9160
And discussion in the meeting today: https://www.w3.org/2023/04/13-openui-minutes.html#t03

[nt1m]

Closing as I think this was fixed by #9171.

@cathiechen Please feel free to reopen if that's not the case.