A notebook cell
Edit the In line; the Out line re-evaluates.
source
<notatio-cell value="1 / 2 + 1 / 3" /><notatio-cell> — a notebook-style In/Out pair: an editable input with its evaluated output beneath, each labelled. The summary line sits above the cell.
value is notatio; the cell converts it to LaTeX for the MathLive field, and what you type there is LaTeX from then on. in-form="latex" skips the conversion and hands the field the value as written; in-form="wolfram" swaps the field for a full-form box.
Edit the In line; the Out line re-evaluates.
<notatio-cell value="1 / 2 + 1 / 3" /><notatio-cell value="Sum(k, (k, 1, n))" /><Cell> is the same element behind a Vue component named for the symbol, whose props are the attributes, typed — generated from the element source, like every other component's (see the playground overview). A markdown author composes Vue and gets a compile-time check on the spelling; the element underneath is unchanged.
<Cell value="Binomial(10, 3) + 1 / 2" out-form="input" />