No bookmark in the PDF yet.  But if you're looking at K-1 package organized and indexed by partner, this has been available since last year.

https://proconnect.intuit.com/support/en-us/help-article/form-1065-schedule-k-1/print-schedule-k-1-p...

Thank you, I knew about the K-1 package and that is great! But I still need bookmarks on the actual return. I have a partnership with 85 partners and when sending it for review it would be easier if it had bookmarks.

I know what you mean.  This is probably one of the most requested features over the years.

It does look like the developers have focused on the higher priority items and should, hopefully, get to this soon, except we know it's definitely not part of the rollout this year.