When a row or column is frozen, the boundary is marked only by a divider line with no accompanying indicator elsewhere in the row or column controls, and the line’s appearance cannot be adjusted using the table’s existing border color or border style options. This makes it difficult to recognize why a boundary line exists or how to change it.

Add a small persistent marker, such as an icon on the row or column handle, wherever a freeze is applied, and extend the existing border color and border style controls so they can also apply to the freeze boundary line.

Benefit: Users can immediately recognize which rows or columns are frozen and adjust the boundary’s appearance using the same controls they already use for the rest of the table.