the aria-required-children rule flags child elements that are not in the accessibility tree as needing to be removed

[stmillMSFT]

Describe the bug

When evaluating the aria-required-children rule, the tool reports elements that are not in the accessibility tree (via aria-hidden=true) as needing to be removed.

Your own docs even list removal from the accessibility tree as a valid way to pass the rule.

But setting aria-hidden="true" on the element (which removes it from the accessibility tree), does not prevent the element from being flagged as needing to be removed.

To Reproduce

Run fastpass on the codepen below. Two false-positives get reported.

CodePen repro example

https://codepen.io/stmill/pen/VwNKLKQ
(this is not quite a minimal repro, since I'm trying to reuse it to repro a related bug as well)

This is also present on this page: https://developer.microsoft.com/en-us/fluentui#/controls/web/detailslist/grouped

Expected behavior

Elements that are not in the accessibility tree should not be included for this rule. The current behavior does not match the aria spec or your own documentation.

Screenshots

Included above.

Context (please complete the following information)

• OS Name & Version: Windows 11 Enterprise 22H2 Build 22621.3296
• AI-Web Version & Environment: 2.41.0
• Browser Version: Edge 122.0.2365.80
• Target Page: Cannot be shared here. If you're a Microsoft FTE, ping me (stmill), and I can share more.

Are you willing to submit a PR?

No

Did you search for similar existing issues?

Yes

Additional context

[DaveTryon]

Let's try to understand what is happening here