When you have problem locating an entry, you are often able drill down from the form (as in this case from Line 64) or by typing in keywords in the search box in the left panel.
The input is under Payments, Penalties & Extensions > Estimated Tax, on the Next Yr. Estimates tab, on the line for Overpayment credit to 2020 (-1=all) {IL}.
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Still an AllStar
