How to get CellHighlightModeSwitch?
import CellHighlightModeSwitch from 'fontoxml-table-flow/src/CellHighlightModeSwitch.jsx'
Create a Switch that activates the special cell highlighting mode. This mode makes it easier to select table cells, at the expense of making it harder to select text. Get the selected cells by using the setCellNodeIdsToHighlightedCells and setBordersByCellNodeIdToHighlightedCells transforms. If you want to apply (styling to) borders you can use set-border-mode-for-highlighted-cells to let the user choose between different border modes.
This button should be in a toolbar that is only visible when the cursor is in a table. It should be placed together with the other options that apply styling based on this selection.