I agree that the same glitch is present this year. I don't own any US bonds or Treasury obligations, and in prior years Line ab of Form 502SU has been blank. This year it lists an amount that's more than 35% of all the interest and dividends I earned in 2020. And there is no way you can determine how TurboTax calculated the number--in the online version, anyway. Perhaps it's different if you use the downloaded software.
If anyone knows a workaround for this issue, please post. Thank you.
