The aria-rowindextext and aria-colindextext properties can be used by developers to express semantics about a table or grid to assistive tech. These attributes are applied in addition to aria-rowindex/aria-colindex in cases where the numeric indices of rows or columns are not meaningful, for example a chessboard or a spreadsheet where the columns are named by letters rather than numbers. These properties are reflected in JavaScript as Element.ariaRowIndexText/Element.ariaColIndexText and ElementInternals.ariaRowIndexText/ElementInternals.ariaColIndexText. These are part of the Interop2024 Accessibility focus area: https://wpt.fyi/results/wai-aria/idlharness.window.html?label=master&label=experimental&aligned&view=interop&q=label%3Ainterop-2024-accessibility