• Green (formula error) and red (error) coloured triangles can occur in a cell (comment).
• A green triangle in a cell's upper-left corner shows that the cell's formula is incorrect. The Trace Error Button image button shows when you pick the cell. For a list of alternatives, click the arrow next to the button.
• The presence of a note in a cell is indicated by a red triangle in the cell's upper-right corner. The text of the note can be viewed by hovering the mouse pointer on the triangle.

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