Update Oct 2020: I searched in Deductions section and was unable to find it when the tool walks you through all deductions, BUT if you select Show Topic List at the top right, scroll to Deductions & Credits > Estimates & Other Taxes Paid > Federal, State and Local Estimates and Federal Taxes Paid and select, it will open window to enter multiple options of which one is that you already sent money with your extension. Enter the amount and the system will estimate how much you still owe, or the amount of refund that you can expect.
