Border below Popover is visible on popover since 2.15.8

[ratrakone]

Describe the bug

i'm still tryin to reproduce on svelte playground, but before the 2.15.8 my popover looked like this

now it has vertical lines goin thru it, which should be the borders of the table below.

Reproduction

wip

Logs

System Info

irrelevant, tested on both mac and windows

Severity

blocking an upgrade

[ratrakone]

found it

https://svelte.dev/playground/d5493097f24d4678be35a3e7abcca3cc?version=5.53.3

we had to implement borders as different divs, that are relative (there are a lot of shenanigans with sticking cols and virutal list etc)
soo relative is no longer below the popover?

[huntabyte]

Oddly enough I'm not seeing anything in that PR that would have changed the style of the Popover.

In the situations where styles/stacking context/etc become problematic I usually wrap the content in Popover.Portal, which solves this issue: https://svelte.dev/playground/6a97599caf4944f29dc7742405a8ac7d?version=5.53.3