New Baseline Low missing pages

[estelle]

Problem statement

There are some very new (2025) features available in all browsers that are not yet documented

Proposed solutions

Document these missing features

Task list

ELEMENT

• api.Element.ariaActiveDescendantElement
• api.Element.ariaControlsElements
• api.Element.ariaDescribedByElements
• api.Element.ariaDetailsElements
• api.Element.ariaErrorMessageElements
• api.Element.ariaFlowToElements
• api.Element.ariaLabelledByElements

ElementInternals

• api.ElementInternals.ariaActiveDescendantElement
• api.ElementInternals.ariaControlsElements
• api.ElementInternals.ariaDescribedByElements
• api.ElementInternals.ariaDetailsElements
• api.ElementInternals.ariaErrorMessageElements
• api.ElementInternals.ariaFlowToElements
• api.ElementInternals.ariaLabelledByElements

CaretPosition

• api.CaretPosition.getClientRect
• api.CaretPosition.offset
• api.CaretPosition.offsetNode