the rule (explained in IRS instructions) is :
a) covered transactions without adjustments do not require Form 8949.
b) covered transactions with adjustments (i.e. wash sales) must be detailed on some 8949 or your other forms in the manner of 8949.
--
If you summarize a) no mailing is necessary
If you summarize b) or,
you summarize other categories either attach (*) or mail in the details .
Box A and Box D are your covered transactions.
a) is the only Exception to the IRS requirement to list in detail every closing transaction you make during the year.
(*) It's been reported TurboTax Online 2020 may prompt you to attach a PDF file of details. But TurboTax CD/Download 2020 will not.
TurboTax 2021 remains to be seen.
