[aria-hidden="true"] elements contain focusable descendants
Unless you are adding custom code to Webflow, this is not going to be a problem.
If you get this error, check Custom Code or Element Settings > Custom Attributes.
Google Lighthouse says
Users of screen readers and other assistive technologies need information about the behavior and purpose of controls on your web page. Native HTML controls like buttons and radio groups come with that information built in. For custom controls you create, however, you must provide the information with ARIA roles and attributes. (Learn more in the Introduction to ARIA.) Using the aria-hidden="true" attribute on an element hides the element and all its children from screen readers and other assistive technologies. If the hidden element contains a focusable element, assistive technologies won't read the focusable element, but keyboard users will still be able to navigate to it, which can cause confusion.