On prod
Basic ->
Tier 1: semantic table, column and row headers, Edit button per row
Headerless ->
Tier 1: td-only table, no header cells and no header styling
Multiple ->
Tier 1: four tables named by heading, caption, following text and position
Spans ->
Tier 2: colspan and rowspan, span-aware and naive reads differ
Editable ->
Tier 2: one unlabelled text input per cell, plus a read-only row
Actions ->
Tier 2: per-row kebab menu and client-side pagination
Nested ->
Tier 2: a complete table inside a cell of another table
Inferred headers ->
Tier 3: headers signalled by styling only
Grid ARIA ->
Tier 3: divs with role=table and friends
Grid divs ->
Tier 3: divs with no semantics and no ARIA, expected to fail