Why does Turbotax fill in my cost basis in column g on form 8283 for donated stocks?

The instructions for form 8283 say Do not complete this column for publicly traded securities held more than 12 months, unless you elect to limit your deduction cost basis. My stocks have been held for more than 12 months. I don't elect to limit my deduction cost basis, but for some reason Turbotax fills in column g with the cost basis.