Function sized_cells_html_into 

pub fn sized_cells_html_into(
    columns: &[Column<'_>],
    sizers: &[Markup<'_>],
    cells: &[Cell<'_>],
    opts: &Emit,
    out: &mut String,
    placed: Option<&mut Vec<Placed>>,
)

A row’s cells with a CELL_SIZER in the columns that have one.

sizers runs parallel to columns: the copies for the column at the same position, empty or missing for a column that has none. The copies are the same in every row, so they are the column’s to pass and not a cell’s, and a column no cell answers still gets them: an empty cell holding no copy would be the one row narrower than the rest.

Written after the cell’s content and inside its block, so a caller passing placed finds them in the block’s range and not in the content’s: they do not vary with the cell. Byte-identical to cells_html_into or cells_html_placed when sizers is empty.