This bug will track how CSS that has scrollbar-color and ::-webkit-scrollbar styles works. Chromiums implementation makes the standard properties take precedence over the legacy pseudos so this behaviour should be matched.
<rdar://problem/110484332>
Pull request: https://github.com/WebKit/WebKit/pull/15196
Committed 265423@main (f056156a42b6): <https://commits.webkit.org/265423@main> Reviewed commits have been landed. Closing PR #15196 and removing active labels.