About

Both grids use a rowHeightProvider (every 13th row 70px, every 5th row 32px, else 25px). Grid A pins the first two columns; Grid B pins the first two columns and the first three rows. The checks assert that the single viewport keeps the provider heights and that both grids expose the expected pinning configuration.

Controls

Run pinning geometry self-checks A: grow row 2 by 10px (invalidateRowHeights) B: grow pinned row 0 by 10px (invalidateRowHeights) Scroll both to row 300