A quick report that v2.3.0 of @github/combobox-nav and the new scrollIntoView broke the UX of @github/text-expander for me. It would push the expanded <ul> to the top of the screen. Also, when I scroll down with the keyboard over the available options (<li> elements), it would try to move the highlighted element to the top of the screen. After spending a few hours debugging what's the core of the issue, I noticed that the undesirable UX happens after the combobox-nav dependency of text-expander is upgraded to v2.3.0.
I think this is the PR that's bugging the behaviour github/combobox-nav#75
If someone else is facing this issue, my solution was to fix combobox-nav to v2.2.0 through "resolutions" section of package.json.