When exporting an intertwined object to PDF the selection trace is preserved in the saved file
Mac OS Ventura 13.0.1 (22A400)
The reproduction scenario is as following:
1. Create two overlaying rings (I used pathfinder to make the hole in the middle).
2. Select both objects
3. Go to Object-Intertwine-Make and select the target area
4. Save in PDF
Even if the Flatten transparency was selected (as suggested in https://illustrator.uservoice.com/forums/601447-illustrator-desktop-bugs/suggestions/45826375-intertwine-bug-when-export-as-pdf-x4 ), the tiny selection trace in the intertwined area can be viewed (see the attached file)
This issue is fixed in the Prerelease version (available in Creative Cloud Desktop Prerelease section).
Intertwine objects now get treated differently when expanded, and an extra copy get placed underneath the stack of clipped zones to eliminate seams PDF viewers display.