showHiddenBorders
By default, showHiddenBorders is set to true. This means that all
tables and table cells with the inline style border:none or
border-style:none will be displayed using a dashed helper line (as
shown in the editor on the left).
Setting this option to false disables the dashed outline for hidden
borders (right example).
showHiddenBordersshowHiddenBorders