If you are not excused by the detail reporting exception,
IRS requires details of your SELL transactions to be supplied on some Form 8949 (with details you enter),
or on your other forms (e.g. consolidated 1099-B or spreadsheet) which have the same information and in the same manner as Form 8949.
If you have details of all your transactions on your e-Filed tax return,
you don't have to mail them again on paper.
you don't have to attach PDF of detail since that is redundant.
Note: To add to the confusion, for Box A or Box D Turbotax may use the detail reporting exception and suppress transactions.
This is recently new undocumented behavior. you are still excused by the exception.
Detail Reporting Exception: if you summarize Box A or Box D, Form 8949 is not needed for transactions without adjustments. No mailing is necessary. No attachment is necessary.
This is the only exception.
@NeoNeo5050
