Comment, or "Sticky" feature
I'd like a way to leave comments on a work in progress, sort of like using a sticky note. For instance, I am working on a choral arrangement of Wayfaring Stranger. It is a lot more complex then anything I have tackled before and, when I get stuck on one part, I often leave it for later and go to some other part. It would be great if there were a way to make notes to myself, reminding me of what I was thinking when I stopped.
Maybe this already exists but I just don't know about it.